diff --git a/src/api/core/accounts.rs b/src/api/core/accounts.rs
index 39654d79..26986c64 100644
--- a/src/api/core/accounts.rs
+++ b/src/api/core/accounts.rs
@@ -79,7 +79,7 @@ pub struct RegisterData {
     name: Option<String>,
     token: Option<String>,
     #[allow(dead_code)]
-    organization_user_id: Option<String>,
+    organization_user_id: Option<MembershipId>,
 }
 
 #[derive(Debug, Deserialize)]
@@ -106,7 +106,7 @@ fn enforce_password_hint_setting(password_hint: &Option<String>) -> EmptyResult
     }
     Ok(())
 }
-async fn is_email_2fa_required(member_uuid: Option<String>, conn: &mut DbConn) -> bool {
+async fn is_email_2fa_required(member_uuid: Option<MembershipId>, conn: &mut DbConn) -> bool {
     if !CONFIG._enable_email_2fa() {
         return false;
     }
diff --git a/src/api/core/events.rs b/src/api/core/events.rs
index a0172ebb..9bd1c806 100644
--- a/src/api/core/events.rs
+++ b/src/api/core/events.rs
@@ -8,7 +8,7 @@ use crate::{
     api::{EmptyResult, JsonResult},
     auth::{AdminHeaders, Headers},
     db::{
-        models::{Cipher, Event, Membership, OrganizationId},
+        models::{Cipher, Event, Membership, MembershipId, OrganizationId},
         DbConn, DbPool,
     },
     util::parse_date,
@@ -93,7 +93,7 @@ async fn get_cipher_events(cipher_id: &str, data: EventRange, headers: Headers,
 #[get("/organizations/<org_id>/users/<member_id>/events?<data..>")]
 async fn get_user_events(
     org_id: &str,
-    member_id: &str,
+    member_id: MembershipId,
     data: EventRange,
     _headers: AdminHeaders,
     mut conn: DbConn,
@@ -110,7 +110,7 @@ async fn get_user_events(
             parse_date(&data.end)
         };
 
-        Event::find_by_org_and_member(org_id, member_id, &start_date, &end_date, &mut conn)
+        Event::find_by_org_and_member(org_id, &member_id, &start_date, &end_date, &mut conn)
             .await
             .iter()
             .map(|e| e.to_json())
diff --git a/src/api/core/organizations.rs b/src/api/core/organizations.rs
index bcfd29a6..ffefcd76 100644
--- a/src/api/core/organizations.rs
+++ b/src/api/core/organizations.rs
@@ -125,7 +125,7 @@ struct OrganizationUpdateData {
 struct NewCollectionData {
     name: String,
     groups: Vec<NewCollectionObjectData>,
-    users: Vec<NewCollectionObjectData>,
+    users: Vec<NewCollectionMemberData>,
     id: Option<String>,
     external_id: Option<String>,
 }
@@ -138,6 +138,14 @@ struct NewCollectionObjectData {
     read_only: bool,
 }
 
+#[derive(Deserialize)]
+#[serde(rename_all = "camelCase")]
+struct NewCollectionMemberData {
+    hide_passwords: bool,
+    id: MembershipId,
+    read_only: bool,
+}
+
 #[derive(Deserialize)]
 #[serde(rename_all = "camelCase")]
 struct OrgKeyData {
@@ -151,6 +159,12 @@ struct OrgBulkIds {
     ids: Vec<String>,
 }
 
+#[derive(Deserialize, Debug)]
+#[serde(rename_all = "camelCase")]
+struct BulkMembershipIds {
+    ids: Vec<MembershipId>,
+}
+
 #[post("/organizations", data = "<data>")]
 async fn create_organization(headers: Headers, data: Json<OrgData>, mut conn: DbConn) -> JsonResult {
     if !CONFIG.is_org_creation_allowed(&headers.user.email) {
@@ -510,7 +524,7 @@ async fn post_organization_collection_update(
 async fn delete_organization_collection_user(
     org_id: OrganizationId,
     col_id: &str,
-    member_id: &str,
+    member_id: MembershipId,
     _headers: AdminHeaders,
     mut conn: DbConn,
 ) -> EmptyResult {
@@ -518,7 +532,7 @@ async fn delete_organization_collection_user(
         err!("Collection not found", "Collection does not exist or does not belong to this organization")
     };
 
-    match Membership::find_by_uuid_and_org(member_id, &org_id, &mut conn).await {
+    match Membership::find_by_uuid_and_org(&member_id, &org_id, &mut conn).await {
         None => err!("User not found in organization"),
         Some(member) => {
             match CollectionUser::find_by_collection_and_user(&collection.uuid, &member.user_uuid, &mut conn).await {
@@ -533,7 +547,7 @@ async fn delete_organization_collection_user(
 async fn post_organization_collection_delete_user(
     org_id: OrganizationId,
     col_id: &str,
-    member_id: &str,
+    member_id: MembershipId,
     headers: AdminHeaders,
     conn: DbConn,
 ) -> EmptyResult {
@@ -827,7 +841,7 @@ async fn post_org_keys(
 #[derive(Deserialize)]
 #[serde(rename_all = "camelCase")]
 struct CollectionData {
-    id: String,
+    id: MembershipId,
     read_only: bool,
     hide_passwords: bool,
 }
@@ -895,11 +909,11 @@ async fn send_invite(
             }
         };
 
-        let mut new_user = Membership::new(user.uuid.clone(), org_id.clone());
+        let mut new_member = Membership::new(user.uuid.clone(), org_id.clone());
         let access_all = data.access_all;
-        new_user.access_all = access_all;
-        new_user.atype = new_type;
-        new_user.status = member_status;
+        new_member.access_all = access_all;
+        new_member.atype = new_type;
+        new_member.status = member_status;
 
         // If no accessAll, add the collections received
         if !access_all {
@@ -920,16 +934,16 @@ async fn send_invite(
             }
         }
 
-        new_user.save(&mut conn).await?;
+        new_member.save(&mut conn).await?;
 
         for group in data.groups.iter() {
-            let mut group_entry = GroupUser::new(String::from(group), user.uuid.clone());
+            let mut group_entry = GroupUser::new(String::from(group), new_member.uuid.clone());
             group_entry.save(&mut conn).await?;
         }
 
         log_event(
             EventType::OrganizationUserInvited as i32,
-            &new_user.uuid,
+            &new_member.uuid,
             &org_id,
             &headers.user.uuid,
             headers.device.atype,
@@ -947,7 +961,7 @@ async fn send_invite(
             mail::send_invite(
                 &user,
                 Some(org_id.clone()),
-                Some(new_user.uuid),
+                Some(new_member.uuid),
                 &org_name,
                 Some(headers.user.email.clone()),
             )
@@ -961,11 +975,11 @@ async fn send_invite(
 #[post("/organizations/<org_id>/users/reinvite", data = "<data>")]
 async fn bulk_reinvite_user(
     org_id: OrganizationId,
-    data: Json<OrgBulkIds>,
+    data: Json<BulkMembershipIds>,
     headers: AdminHeaders,
     mut conn: DbConn,
 ) -> Json<Value> {
-    let data: OrgBulkIds = data.into_inner();
+    let data: BulkMembershipIds = data.into_inner();
 
     let mut bulk_response = Vec::new();
     for member_id in data.ids {
@@ -990,18 +1004,23 @@ async fn bulk_reinvite_user(
     }))
 }
 
-#[post("/organizations/<org_id>/users/<member>/reinvite")]
-async fn reinvite_user(org_id: OrganizationId, member: &str, headers: AdminHeaders, mut conn: DbConn) -> EmptyResult {
-    _reinvite_user(&org_id, member, &headers.user.email, &mut conn).await
+#[post("/organizations/<org_id>/users/<member_id>/reinvite")]
+async fn reinvite_user(
+    org_id: OrganizationId,
+    member_id: MembershipId,
+    headers: AdminHeaders,
+    mut conn: DbConn,
+) -> EmptyResult {
+    _reinvite_user(&org_id, &member_id, &headers.user.email, &mut conn).await
 }
 
 async fn _reinvite_user(
     org_id: &OrganizationId,
-    member: &str,
+    member_id: &MembershipId,
     invited_by_email: &str,
     conn: &mut DbConn,
 ) -> EmptyResult {
-    let Some(member) = Membership::find_by_uuid_and_org(member, org_id, conn).await else {
+    let Some(member) = Membership::find_by_uuid_and_org(member_id, org_id, conn).await else {
         err!("The user hasn't been invited to the organization.")
     };
 
@@ -1054,7 +1073,7 @@ struct AcceptData {
 #[post("/organizations/<org_id>/users/<member_id>/accept", data = "<data>")]
 async fn accept_invite(
     org_id: OrganizationId,
-    member_id: &str,
+    member_id: MembershipId,
     data: Json<AcceptData>,
     mut conn: DbConn,
 ) -> EmptyResult {
@@ -1064,7 +1083,7 @@ async fn accept_invite(
 
     // If a claim does not have a member_id or it does not match the one in from the URI, something is wrong.
     match &claims.member_id {
-        Some(ou_id) if ou_id.eq(member_id) => {}
+        Some(ou_id) if ou_id.eq(&member_id) => {}
         _ => err!("Error accepting the invitation", "Claim does not match the member_id"),
     }
 
@@ -1139,7 +1158,7 @@ async fn accept_invite(
 #[derive(Deserialize)]
 #[serde(rename_all = "camelCase")]
 struct ConfirmData {
-    id: Option<String>,
+    id: Option<MembershipId>,
     key: Option<String>,
 }
 
@@ -1163,7 +1182,7 @@ async fn bulk_confirm_invite(
     match data.keys {
         Some(keys) => {
             for invite in keys {
-                let member_id = invite.id.unwrap_or_default();
+                let member_id = invite.id.unwrap();
                 let user_key = invite.key.unwrap_or_default();
                 let err_msg = match _confirm_invite(&org_id, &member_id, &user_key, &headers, &mut conn, &nt).await {
                     Ok(_) => String::new(),
@@ -1192,7 +1211,7 @@ async fn bulk_confirm_invite(
 #[post("/organizations/<org_id>/users/<member_id>/confirm", data = "<data>")]
 async fn confirm_invite(
     org_id: OrganizationId,
-    member_id: &str,
+    member_id: MembershipId,
     data: Json<ConfirmData>,
     headers: AdminHeaders,
     mut conn: DbConn,
@@ -1200,12 +1219,12 @@ async fn confirm_invite(
 ) -> EmptyResult {
     let data = data.into_inner();
     let user_key = data.key.unwrap_or_default();
-    _confirm_invite(&org_id, member_id, &user_key, &headers, &mut conn, &nt).await
+    _confirm_invite(&org_id, &member_id, &user_key, &headers, &mut conn, &nt).await
 }
 
 async fn _confirm_invite(
     org_id: &OrganizationId,
-    member_id: &str,
+    member_id: &MembershipId,
     key: &str,
     headers: &AdminHeaders,
     conn: &mut DbConn,
@@ -1283,12 +1302,12 @@ async fn _confirm_invite(
 #[get("/organizations/<org_id>/users/<member_id>?<data..>")]
 async fn get_user(
     org_id: OrganizationId,
-    member_id: &str,
+    member_id: MembershipId,
     data: GetOrgUserData,
     _headers: AdminHeaders,
     mut conn: DbConn,
 ) -> JsonResult {
-    let Some(user) = Membership::find_by_uuid_and_org(member_id, &org_id, &mut conn).await else {
+    let Some(user) = Membership::find_by_uuid_and_org(&member_id, &org_id, &mut conn).await else {
         err!("The specified user isn't a member of the organization")
     };
 
@@ -1313,7 +1332,7 @@ struct EditUserData {
 #[put("/organizations/<org_id>/users/<member_id>", data = "<data>", rank = 1)]
 async fn put_membership(
     org_id: OrganizationId,
-    member_id: &str,
+    member_id: MembershipId,
     data: Json<EditUserData>,
     headers: AdminHeaders,
     conn: DbConn,
@@ -1324,7 +1343,7 @@ async fn put_membership(
 #[post("/organizations/<org_id>/users/<member_id>", data = "<data>", rank = 1)]
 async fn edit_user(
     org_id: OrganizationId,
-    member_id: &str,
+    member_id: MembershipId,
     data: Json<EditUserData>,
     headers: AdminHeaders,
     mut conn: DbConn,
@@ -1335,7 +1354,7 @@ async fn edit_user(
         err!("Invalid type")
     };
 
-    let Some(mut member_to_edit) = Membership::find_by_uuid_and_org(member_id, &org_id, &mut conn).await else {
+    let Some(mut member_to_edit) = Membership::find_by_uuid_and_org(&member_id, &org_id, &mut conn).await else {
         err!("The specified user isn't member of the organization")
     };
 
@@ -1429,12 +1448,12 @@ async fn edit_user(
 #[delete("/organizations/<org_id>/users", data = "<data>")]
 async fn bulk_delete_user(
     org_id: OrganizationId,
-    data: Json<OrgBulkIds>,
+    data: Json<BulkMembershipIds>,
     headers: AdminHeaders,
     mut conn: DbConn,
     nt: Notify<'_>,
 ) -> Json<Value> {
-    let data: OrgBulkIds = data.into_inner();
+    let data: BulkMembershipIds = data.into_inner();
 
     let mut bulk_response = Vec::new();
     for member_id in data.ids {
@@ -1462,28 +1481,28 @@ async fn bulk_delete_user(
 #[delete("/organizations/<org_id>/users/<member_id>")]
 async fn delete_user(
     org_id: OrganizationId,
-    member_id: &str,
+    member_id: MembershipId,
     headers: AdminHeaders,
     mut conn: DbConn,
     nt: Notify<'_>,
 ) -> EmptyResult {
-    _delete_user(&org_id, member_id, &headers, &mut conn, &nt).await
+    _delete_user(&org_id, &member_id, &headers, &mut conn, &nt).await
 }
 
 #[post("/organizations/<org_id>/users/<member_id>/delete")]
 async fn post_delete_user(
     org_id: OrganizationId,
-    member_id: &str,
+    member_id: MembershipId,
     headers: AdminHeaders,
     mut conn: DbConn,
     nt: Notify<'_>,
 ) -> EmptyResult {
-    _delete_user(&org_id, member_id, &headers, &mut conn, &nt).await
+    _delete_user(&org_id, &member_id, &headers, &mut conn, &nt).await
 }
 
 async fn _delete_user(
     org_id: &OrganizationId,
-    member_id: &str,
+    member_id: &MembershipId,
     headers: &AdminHeaders,
     conn: &mut DbConn,
     nt: &Notify<'_>,
@@ -1525,11 +1544,11 @@ async fn _delete_user(
 #[post("/organizations/<org_id>/users/public-keys", data = "<data>")]
 async fn bulk_public_keys(
     org_id: OrganizationId,
-    data: Json<OrgBulkIds>,
+    data: Json<BulkMembershipIds>,
     _headers: AdminHeaders,
     mut conn: DbConn,
 ) -> Json<Value> {
-    let data: OrgBulkIds = data.into_inner();
+    let data: BulkMembershipIds = data.into_inner();
 
     let mut bulk_response = Vec::new();
     // Check all received Membership UUID's and find the matching User to retrieve the public-key.
@@ -2074,18 +2093,24 @@ async fn import(org_id: OrganizationId, data: Json<OrgImportData>, headers: Head
 #[put("/organizations/<org_id>/users/<member_id>/deactivate")]
 async fn deactivate_membership(
     org_id: OrganizationId,
-    member_id: &str,
+    member_id: MembershipId,
     headers: AdminHeaders,
     mut conn: DbConn,
 ) -> EmptyResult {
-    _revoke_membership(&org_id, member_id, &headers, &mut conn).await
+    _revoke_membership(&org_id, &member_id, &headers, &mut conn).await
+}
+
+#[derive(Deserialize, Debug)]
+#[serde(rename_all = "camelCase")]
+struct BulkRevokeMembershipIds {
+    ids: Option<Vec<MembershipId>>,
 }
 
 // Pre web-vault v2022.9.x endpoint
 #[put("/organizations/<org_id>/users/deactivate", data = "<data>")]
 async fn bulk_deactivate_membership(
     org_id: OrganizationId,
-    data: Json<OrgBulkRevokeData>,
+    data: Json<BulkRevokeMembershipIds>,
     headers: AdminHeaders,
     conn: DbConn,
 ) -> Json<Value> {
@@ -2095,23 +2120,17 @@ async fn bulk_deactivate_membership(
 #[put("/organizations/<org_id>/users/<member_id>/revoke")]
 async fn revoke_membership(
     org_id: OrganizationId,
-    member_id: &str,
+    member_id: MembershipId,
     headers: AdminHeaders,
     mut conn: DbConn,
 ) -> EmptyResult {
-    _revoke_membership(&org_id, member_id, &headers, &mut conn).await
-}
-
-#[derive(Deserialize, Debug)]
-#[serde(rename_all = "camelCase")]
-struct OrgBulkRevokeData {
-    ids: Option<Vec<String>>,
+    _revoke_membership(&org_id, &member_id, &headers, &mut conn).await
 }
 
 #[put("/organizations/<org_id>/users/revoke", data = "<data>")]
 async fn bulk_revoke_membership(
     org_id: OrganizationId,
-    data: Json<OrgBulkRevokeData>,
+    data: Json<BulkRevokeMembershipIds>,
     headers: AdminHeaders,
     mut conn: DbConn,
 ) -> Json<Value> {
@@ -2147,7 +2166,7 @@ async fn bulk_revoke_membership(
 
 async fn _revoke_membership(
     org_id: &OrganizationId,
-    member_id: &str,
+    member_id: &MembershipId,
     headers: &AdminHeaders,
     conn: &mut DbConn,
 ) -> EmptyResult {
@@ -2189,18 +2208,18 @@ async fn _revoke_membership(
 #[put("/organizations/<org_id>/users/<member_id>/activate")]
 async fn activate_membership(
     org_id: OrganizationId,
-    member_id: &str,
+    member_id: MembershipId,
     headers: AdminHeaders,
     mut conn: DbConn,
 ) -> EmptyResult {
-    _restore_membership(&org_id, member_id, &headers, &mut conn).await
+    _restore_membership(&org_id, &member_id, &headers, &mut conn).await
 }
 
 // Pre web-vault v2022.9.x endpoint
 #[put("/organizations/<org_id>/users/activate", data = "<data>")]
 async fn bulk_activate_membership(
     org_id: OrganizationId,
-    data: Json<OrgBulkIds>,
+    data: Json<BulkMembershipIds>,
     headers: AdminHeaders,
     conn: DbConn,
 ) -> Json<Value> {
@@ -2210,17 +2229,17 @@ async fn bulk_activate_membership(
 #[put("/organizations/<org_id>/users/<member_id>/restore")]
 async fn restore_membership(
     org_id: OrganizationId,
-    member_id: &str,
+    member_id: MembershipId,
     headers: AdminHeaders,
     mut conn: DbConn,
 ) -> EmptyResult {
-    _restore_membership(&org_id, member_id, &headers, &mut conn).await
+    _restore_membership(&org_id, &member_id, &headers, &mut conn).await
 }
 
 #[put("/organizations/<org_id>/users/restore", data = "<data>")]
 async fn bulk_restore_membership(
     org_id: OrganizationId,
-    data: Json<OrgBulkIds>,
+    data: Json<BulkMembershipIds>,
     headers: AdminHeaders,
     mut conn: DbConn,
 ) -> Json<Value> {
@@ -2251,7 +2270,7 @@ async fn bulk_restore_membership(
 
 async fn _restore_membership(
     org_id: &OrganizationId,
-    member_id: &str,
+    member_id: &MembershipId,
     headers: &AdminHeaders,
     conn: &mut DbConn,
 ) -> EmptyResult {
@@ -2334,7 +2353,7 @@ struct GroupRequest {
     access_all: bool,
     external_id: Option<String>,
     collections: Vec<SelectionReadOnly>,
-    users: Vec<String>,
+    users: Vec<MembershipId>,
 }
 
 impl GroupRequest {
@@ -2464,7 +2483,7 @@ async fn put_group(
 async fn add_update_group(
     mut group: Group,
     collections: Vec<SelectionReadOnly>,
-    users: Vec<String>,
+    members: Vec<MembershipId>,
     org_id: OrganizationId,
     headers: &AdminHeaders,
     conn: &mut DbConn,
@@ -2476,13 +2495,13 @@ async fn add_update_group(
         collection_group.save(conn).await?;
     }
 
-    for assigned_user_id in users {
-        let mut user_entry = GroupUser::new(group.uuid.clone(), assigned_user_id.clone());
+    for assigned_member in members {
+        let mut user_entry = GroupUser::new(group.uuid.clone(), assigned_member.clone());
         user_entry.save(conn).await?;
 
         log_event(
             EventType::OrganizationUserUpdatedGroups as i32,
-            &assigned_user_id,
+            &assigned_member,
             &org_id,
             &headers.user.uuid,
             headers.device.atype,
@@ -2609,7 +2628,7 @@ async fn get_group_users(
         err!("Group could not be found!", "Group uuid is invalid or does not belong to the organization")
     };
 
-    let group_users: Vec<String> = GroupUser::find_by_group(group_id, &mut conn)
+    let group_users: Vec<MembershipId> = GroupUser::find_by_group(group_id, &mut conn)
         .await
         .iter()
         .map(|entry| entry.users_organizations_uuid.clone())
@@ -2623,7 +2642,7 @@ async fn put_group_users(
     org_id: OrganizationId,
     group_id: &str,
     headers: AdminHeaders,
-    data: Json<Vec<String>>,
+    data: Json<Vec<MembershipId>>,
     mut conn: DbConn,
 ) -> EmptyResult {
     if !CONFIG.org_groups_enabled() {
@@ -2636,14 +2655,14 @@ async fn put_group_users(
 
     GroupUser::delete_all_by_group(group_id, &mut conn).await?;
 
-    let assigned_user_ids = data.into_inner();
-    for assigned_user_id in assigned_user_ids {
-        let mut user_entry = GroupUser::new(String::from(group_id), assigned_user_id.clone());
+    let assigned_members = data.into_inner();
+    for assigned_member in assigned_members {
+        let mut user_entry = GroupUser::new(String::from(group_id), assigned_member.clone());
         user_entry.save(&mut conn).await?;
 
         log_event(
             EventType::OrganizationUserUpdatedGroups as i32,
-            &assigned_user_id,
+            &assigned_member,
             &org_id,
             &headers.user.uuid,
             headers.device.atype,
@@ -2656,10 +2675,10 @@ async fn put_group_users(
     Ok(())
 }
 
-#[get("/organizations/<org_id>/users/<user_id>/groups")]
+#[get("/organizations/<org_id>/users/<member_id>/groups")]
 async fn get_user_groups(
     org_id: OrganizationId,
-    user_id: &str,
+    member_id: MembershipId,
     _headers: AdminHeaders,
     mut conn: DbConn,
 ) -> JsonResult {
@@ -2667,12 +2686,12 @@ async fn get_user_groups(
         err!("Group support is disabled");
     }
 
-    if Membership::find_by_uuid_and_org(user_id, &org_id, &mut conn).await.is_none() {
+    if Membership::find_by_uuid_and_org(&member_id, &org_id, &mut conn).await.is_none() {
         err!("User could not be found!")
     };
 
     let user_groups: Vec<String> =
-        GroupUser::find_by_user(user_id, &mut conn).await.iter().map(|entry| entry.groups_uuid.clone()).collect();
+        GroupUser::find_by_member(&member_id, &mut conn).await.iter().map(|entry| entry.groups_uuid.clone()).collect();
 
     Ok(Json(json!(user_groups)))
 }
@@ -2686,7 +2705,7 @@ struct OrganizationUserUpdateGroupsRequest {
 #[post("/organizations/<org_id>/users/<member_id>/groups", data = "<data>")]
 async fn post_user_groups(
     org_id: OrganizationId,
-    member_id: &str,
+    member_id: MembershipId,
     data: Json<OrganizationUserUpdateGroupsRequest>,
     headers: AdminHeaders,
     conn: DbConn,
@@ -2697,7 +2716,7 @@ async fn post_user_groups(
 #[put("/organizations/<org_id>/users/<member_id>/groups", data = "<data>")]
 async fn put_user_groups(
     org_id: OrganizationId,
-    member_id: &str,
+    member_id: MembershipId,
     data: Json<OrganizationUserUpdateGroupsRequest>,
     headers: AdminHeaders,
     mut conn: DbConn,
@@ -2706,7 +2725,7 @@ async fn put_user_groups(
         err!("Group support is disabled");
     }
 
-    if Membership::find_by_uuid_and_org(member_id, &org_id, &mut conn).await.is_none() {
+    if Membership::find_by_uuid_and_org(&member_id, &org_id, &mut conn).await.is_none() {
         err!("User could not be found or does not belong to the organization.");
     }
 
@@ -2714,13 +2733,13 @@ async fn put_user_groups(
 
     let assigned_group_ids = data.into_inner();
     for assigned_group_id in assigned_group_ids.group_ids {
-        let mut group_user = GroupUser::new(assigned_group_id.clone(), String::from(member_id));
+        let mut group_user = GroupUser::new(assigned_group_id.clone(), member_id.clone());
         group_user.save(&mut conn).await?;
     }
 
     log_event(
         EventType::OrganizationUserUpdatedGroups as i32,
-        member_id,
+        &member_id,
         &org_id,
         &headers.user.uuid,
         headers.device.atype,
@@ -2736,7 +2755,7 @@ async fn put_user_groups(
 async fn post_delete_group_user(
     org_id: OrganizationId,
     group_id: &str,
-    member_id: &str,
+    member_id: MembershipId,
     headers: AdminHeaders,
     conn: DbConn,
 ) -> EmptyResult {
@@ -2747,7 +2766,7 @@ async fn post_delete_group_user(
 async fn delete_group_user(
     org_id: OrganizationId,
     group_id: &str,
-    member_id: &str,
+    member_id: MembershipId,
     headers: AdminHeaders,
     mut conn: DbConn,
 ) -> EmptyResult {
@@ -2755,7 +2774,7 @@ async fn delete_group_user(
         err!("Group support is disabled");
     }
 
-    if Membership::find_by_uuid_and_org(member_id, &org_id, &mut conn).await.is_none() {
+    if Membership::find_by_uuid_and_org(&member_id, &org_id, &mut conn).await.is_none() {
         err!("User could not be found or does not belong to the organization.");
     }
 
@@ -2765,7 +2784,7 @@ async fn delete_group_user(
 
     log_event(
         EventType::OrganizationUserUpdatedGroups as i32,
-        member_id,
+        &member_id,
         &org_id,
         &headers.user.uuid,
         headers.device.atype,
@@ -2774,7 +2793,7 @@ async fn delete_group_user(
     )
     .await;
 
-    GroupUser::delete_by_group_id_and_user_id(group_id, member_id, &mut conn).await
+    GroupUser::delete_by_group_and_member(group_id, &member_id, &mut conn).await
 }
 
 #[derive(Deserialize)]
@@ -2817,7 +2836,7 @@ async fn get_organization_keys(org_id: OrganizationId, headers: Headers, conn: D
 #[put("/organizations/<org_id>/users/<member_id>/reset-password", data = "<data>")]
 async fn put_reset_password(
     org_id: OrganizationId,
-    member_id: &str,
+    member_id: MembershipId,
     headers: AdminHeaders,
     data: Json<OrganizationUserResetPasswordRequest>,
     mut conn: DbConn,
@@ -2827,7 +2846,7 @@ async fn put_reset_password(
         err!("Required organization not found")
     };
 
-    let Some(member) = Membership::find_by_uuid_and_org(member_id, &org.uuid, &mut conn).await else {
+    let Some(member) = Membership::find_by_uuid_and_org(&member_id, &org.uuid, &mut conn).await else {
         err!("User to reset isn't member of required organization")
     };
 
@@ -2835,7 +2854,7 @@ async fn put_reset_password(
         err!("User not found")
     };
 
-    check_reset_password_applicable_and_permissions(&org_id, member_id, &headers, &mut conn).await?;
+    check_reset_password_applicable_and_permissions(&org_id, &member_id, &headers, &mut conn).await?;
 
     if member.reset_password_key.is_none() {
         err!("Password reset not or not correctly enrolled");
@@ -2860,7 +2879,7 @@ async fn put_reset_password(
 
     log_event(
         EventType::OrganizationUserAdminResetPassword as i32,
-        member_id,
+        &member_id,
         &org_id,
         &headers.user.uuid,
         headers.device.atype,
@@ -2875,7 +2894,7 @@ async fn put_reset_password(
 #[get("/organizations/<org_id>/users/<member_id>/reset-password-details")]
 async fn get_reset_password_details(
     org_id: OrganizationId,
-    member_id: &str,
+    member_id: MembershipId,
     headers: AdminHeaders,
     mut conn: DbConn,
 ) -> JsonResult {
@@ -2883,7 +2902,7 @@ async fn get_reset_password_details(
         err!("Required organization not found")
     };
 
-    let Some(member) = Membership::find_by_uuid_and_org(member_id, &org_id, &mut conn).await else {
+    let Some(member) = Membership::find_by_uuid_and_org(&member_id, &org_id, &mut conn).await else {
         err!("User to reset isn't member of required organization")
     };
 
@@ -2891,7 +2910,7 @@ async fn get_reset_password_details(
         err!("User not found")
     };
 
-    check_reset_password_applicable_and_permissions(&org_id, member_id, &headers, &mut conn).await?;
+    check_reset_password_applicable_and_permissions(&org_id, &member_id, &headers, &mut conn).await?;
 
     // https://github.com/bitwarden/server/blob/3b50ccb9f804efaacdc46bed5b60e5b28eddefcf/src/Api/Models/Response/Organizations/OrganizationUserResponseModel.cs#L111
     Ok(Json(json!({
@@ -2908,7 +2927,7 @@ async fn get_reset_password_details(
 
 async fn check_reset_password_applicable_and_permissions(
     org_id: &OrganizationId,
-    member_id: &str,
+    member_id: &MembershipId,
     headers: &AdminHeaders,
     conn: &mut DbConn,
 ) -> EmptyResult {
@@ -2945,7 +2964,7 @@ async fn check_reset_password_applicable(org_id: &OrganizationId, conn: &mut DbC
 #[put("/organizations/<org_id>/users/<member_id>/reset-password-enrollment", data = "<data>")]
 async fn put_reset_password_enrollment(
     org_id: OrganizationId,
-    member_id: &str,
+    member_id: MembershipId,
     headers: Headers,
     data: Json<OrganizationUserResetPasswordEnrollmentRequest>,
     mut conn: DbConn,
@@ -2982,7 +3001,7 @@ async fn put_reset_password_enrollment(
         EventType::OrganizationUserResetPasswordWithdraw as i32
     };
 
-    log_event(log_id, member_id, &org_id, &headers.user.uuid, headers.device.atype, &headers.ip.ip, &mut conn).await;
+    log_event(log_id, &member_id, &org_id, &headers.user.uuid, headers.device.atype, &headers.ip.ip, &mut conn).await;
 
     Ok(())
 }
diff --git a/src/auth.rs b/src/auth.rs
index a2cbc9ee..e09d6161 100644
--- a/src/auth.rs
+++ b/src/auth.rs
@@ -14,7 +14,7 @@ use std::{
     net::IpAddr,
 };
 
-use crate::db::models::OrganizationId;
+use crate::db::models::{MembershipId, OrganizationId};
 use crate::{error::Error, CONFIG};
 
 const JWT_ALGORITHM: Algorithm = Algorithm::RS256;
@@ -192,7 +192,7 @@ pub struct InviteJwtClaims {
 
     pub email: String,
     pub org_id: Option<OrganizationId>,
-    pub member_id: Option<String>,
+    pub member_id: Option<MembershipId>,
     pub invited_by_email: Option<String>,
 }
 
@@ -200,7 +200,7 @@ pub fn generate_invite_claims(
     uuid: String,
     email: String,
     org_id: Option<OrganizationId>,
-    member_id: Option<String>,
+    member_id: Option<MembershipId>,
     invited_by_email: Option<String>,
 ) -> InviteJwtClaims {
     let time_now = Utc::now();
diff --git a/src/db/models/group.rs b/src/db/models/group.rs
index aeb8502a..c0a31761 100644
--- a/src/db/models/group.rs
+++ b/src/db/models/group.rs
@@ -1,4 +1,4 @@
-use super::{Membership, OrganizationId, User};
+use super::{Membership, MembershipId, OrganizationId, User};
 use crate::api::EmptyResult;
 use crate::db::DbConn;
 use crate::error::MapResult;
@@ -34,7 +34,7 @@ db_object! {
     #[diesel(primary_key(groups_uuid, users_organizations_uuid))]
     pub struct GroupUser {
         pub groups_uuid: String,
-        pub users_organizations_uuid: String
+        pub users_organizations_uuid: MembershipId
     }
 }
 
@@ -124,7 +124,7 @@ impl CollectionGroup {
 }
 
 impl GroupUser {
-    pub fn new(groups_uuid: String, users_organizations_uuid: String) -> Self {
+    pub fn new(groups_uuid: String, users_organizations_uuid: MembershipId) -> Self {
         Self {
             groups_uuid,
             users_organizations_uuid,
@@ -485,10 +485,10 @@ impl GroupUser {
         }}
     }
 
-    pub async fn find_by_user(users_organizations_uuid: &str, conn: &mut DbConn) -> Vec<Self> {
+    pub async fn find_by_member(member_uuid: &MembershipId, conn: &mut DbConn) -> Vec<Self> {
         db_run! { conn: {
             groups_users::table
-                .filter(groups_users::users_organizations_uuid.eq(users_organizations_uuid))
+                .filter(groups_users::users_organizations_uuid.eq(member_uuid))
                 .load::<GroupUserDb>(conn)
                 .expect("Error loading groups for user")
                 .from_db()
@@ -497,7 +497,7 @@ impl GroupUser {
 
     pub async fn has_access_to_collection_by_member(
         collection_uuid: &str,
-        member_uuid: &str,
+        member_uuid: &MembershipId,
         conn: &mut DbConn,
     ) -> bool {
         db_run! { conn: {
@@ -513,7 +513,11 @@ impl GroupUser {
         }}
     }
 
-    pub async fn has_full_access_by_member(org_uuid: &OrganizationId, member_uuid: &str, conn: &mut DbConn) -> bool {
+    pub async fn has_full_access_by_member(
+        org_uuid: &OrganizationId,
+        member_uuid: &MembershipId,
+        conn: &mut DbConn,
+    ) -> bool {
         db_run! { conn: {
             groups_users::table
                 .inner_join(groups::table.on(
@@ -535,12 +539,12 @@ impl GroupUser {
         }
     }
 
-    pub async fn delete_by_group_id_and_user_id(
+    pub async fn delete_by_group_and_member(
         group_uuid: &str,
-        users_organizations_uuid: &str,
+        member_uuid: &MembershipId,
         conn: &mut DbConn,
     ) -> EmptyResult {
-        match Membership::find_by_uuid(users_organizations_uuid, conn).await {
+        match Membership::find_by_uuid(member_uuid, conn).await {
             Some(member) => User::update_uuid_revision(&member.user_uuid, conn).await,
             None => warn!("Member could not be found!"),
         };
@@ -548,7 +552,7 @@ impl GroupUser {
         db_run! { conn: {
             diesel::delete(groups_users::table)
                 .filter(groups_users::groups_uuid.eq(group_uuid))
-                .filter(groups_users::users_organizations_uuid.eq(users_organizations_uuid))
+                .filter(groups_users::users_organizations_uuid.eq(member_uuid))
                 .execute(conn)
                 .map_res("Error deleting group users")
         }}
@@ -568,7 +572,7 @@ impl GroupUser {
         }}
     }
 
-    pub async fn delete_all_by_member(member_uuid: &str, conn: &mut DbConn) -> EmptyResult {
+    pub async fn delete_all_by_member(member_uuid: &MembershipId, conn: &mut DbConn) -> EmptyResult {
         match Membership::find_by_uuid(member_uuid, conn).await {
             Some(member) => User::update_uuid_revision(&member.user_uuid, conn).await,
             None => warn!("Member could not be found!"),
diff --git a/src/db/models/mod.rs b/src/db/models/mod.rs
index 69b7460e..fe61e42f 100644
--- a/src/db/models/mod.rs
+++ b/src/db/models/mod.rs
@@ -28,7 +28,7 @@ pub use self::folder::{Folder, FolderCipher};
 pub use self::group::{CollectionGroup, Group, GroupUser};
 pub use self::org_policy::{OrgPolicy, OrgPolicyErr, OrgPolicyType};
 pub use self::organization::{
-    Membership, MembershipStatus, MembershipType, Organization, OrganizationApiKey, OrganizationId,
+    Membership, MembershipId, MembershipStatus, MembershipType, Organization, OrganizationApiKey, OrganizationId,
 };
 pub use self::send::{Send, SendType};
 pub use self::two_factor::{TwoFactor, TwoFactorType};
diff --git a/src/db/models/org_policy.rs b/src/db/models/org_policy.rs
index f0a99d24..c63fa16d 100644
--- a/src/db/models/org_policy.rs
+++ b/src/db/models/org_policy.rs
@@ -5,7 +5,7 @@ use crate::api::EmptyResult;
 use crate::db::DbConn;
 use crate::error::MapResult;
 
-use super::{Membership, MembershipStatus, MembershipType, OrganizationId, TwoFactor};
+use super::{Membership, MembershipId, MembershipStatus, MembershipType, OrganizationId, TwoFactor};
 
 db_object! {
     #[derive(Identifiable, Queryable, Insertable, AsChangeset)]
@@ -336,7 +336,11 @@ impl OrgPolicy {
         false
     }
 
-    pub async fn is_enabled_for_member(member_uuid: &str, policy_type: OrgPolicyType, conn: &mut DbConn) -> bool {
+    pub async fn is_enabled_for_member(
+        member_uuid: &MembershipId,
+        policy_type: OrgPolicyType,
+        conn: &mut DbConn,
+    ) -> bool {
         if let Some(member) = Membership::find_by_uuid(member_uuid, conn).await {
             if let Some(policy) = OrgPolicy::find_by_org_and_type(&member.org_uuid, policy_type, conn).await {
                 return policy.enabled;
diff --git a/src/db/models/organization.rs b/src/db/models/organization.rs
index 73a86b7f..7a3657ed 100644
--- a/src/db/models/organization.rs
+++ b/src/db/models/organization.rs
@@ -30,7 +30,7 @@ db_object! {
     #[diesel(table_name = users_organizations)]
     #[diesel(primary_key(uuid))]
     pub struct Membership {
-        pub uuid: String,
+        pub uuid: MembershipId,
         pub user_uuid: String,
         pub org_uuid: OrganizationId,
 
@@ -206,7 +206,7 @@ static ACTIVATE_REVOKE_DIFF: i32 = 128;
 impl Membership {
     pub fn new(user_uuid: String, org_uuid: OrganizationId) -> Self {
         Self {
-            uuid: crate::util::get_uuid(),
+            uuid: MembershipId(crate::util::get_uuid()),
 
             user_uuid,
             org_uuid,
@@ -459,7 +459,7 @@ impl Membership {
         let twofactor_enabled = !TwoFactor::find_by_user(&user.uuid, conn).await.is_empty();
 
         let groups: Vec<String> = if include_groups && CONFIG.org_groups_enabled() {
-            GroupUser::find_by_user(&self.uuid, conn).await.iter().map(|gu| gu.groups_uuid.clone()).collect()
+            GroupUser::find_by_member(&self.uuid, conn).await.iter().map(|gu| gu.groups_uuid.clone()).collect()
         } else {
             // The Bitwarden clients seem to call this API regardless of whether groups are enabled,
             // so just act as if there are no groups.
@@ -699,7 +699,7 @@ impl Membership {
         (self.access_all || self.atype >= MembershipType::Admin) && self.has_status(MembershipStatus::Confirmed)
     }
 
-    pub async fn find_by_uuid(uuid: &str, conn: &mut DbConn) -> Option<Self> {
+    pub async fn find_by_uuid(uuid: &MembershipId, conn: &mut DbConn) -> Option<Self> {
         db_run! { conn: {
             users_organizations::table
                 .filter(users_organizations::uuid.eq(uuid))
@@ -708,7 +708,11 @@ impl Membership {
         }}
     }
 
-    pub async fn find_by_uuid_and_org(uuid: &str, org_uuid: &OrganizationId, conn: &mut DbConn) -> Option<Self> {
+    pub async fn find_by_uuid_and_org(
+        uuid: &MembershipId,
+        org_uuid: &OrganizationId,
+        conn: &mut DbConn,
+    ) -> Option<Self> {
         db_run! { conn: {
             users_organizations::table
                 .filter(users_organizations::uuid.eq(uuid))
@@ -1078,16 +1082,61 @@ impl<'r> FromParam<'r> for OrganizationId {
     #[inline(always)]
     fn from_param(param: &'r str) -> Result<Self, Self::Error> {
         if param.chars().all(|c| matches!(c, 'a'..='z' | 'A'..='Z' |'0'..='9' | '-')) {
-            Ok(OrganizationId(param.to_string()))
+            Ok(Self(param.to_string()))
         } else {
             Err(())
         }
     }
 }
 
-#[derive(DieselNewType, Clone, Debug, Hash, PartialEq, Eq, Serialize)]
+#[derive(DieselNewType, FromForm, Clone, Debug, Hash, PartialEq, Eq, Serialize, Deserialize)]
 pub struct MembershipId(String);
 
+impl AsRef<str> for MembershipId {
+    fn as_ref(&self) -> &str {
+        &self.0
+    }
+}
+
+impl Deref for MembershipId {
+    type Target = str;
+
+    fn deref(&self) -> &Self::Target {
+        &self.0
+    }
+}
+
+impl Borrow<str> for MembershipId {
+    fn borrow(&self) -> &str {
+        &self.0
+    }
+}
+
+impl Display for MembershipId {
+    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
+        write!(f, "{}", self.0)
+    }
+}
+
+impl From<String> for MembershipId {
+    fn from(raw: String) -> Self {
+        Self(raw)
+    }
+}
+
+impl<'r> FromParam<'r> for MembershipId {
+    type Error = ();
+
+    #[inline(always)]
+    fn from_param(param: &'r str) -> Result<Self, Self::Error> {
+        if param.chars().all(|c| matches!(c, 'a'..='z' | 'A'..='Z' |'0'..='9' | '-')) {
+            Ok(Self(param.to_string()))
+        } else {
+            Err(())
+        }
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
diff --git a/src/mail.rs b/src/mail.rs
index e1c8c6da..126adace 100644
--- a/src/mail.rs
+++ b/src/mail.rs
@@ -17,7 +17,7 @@ use crate::{
         encode_jwt, generate_delete_claims, generate_emergency_access_invite_claims, generate_invite_claims,
         generate_verify_email_claims,
     },
-    db::models::{Device, DeviceType, OrganizationId, User},
+    db::models::{Device, DeviceType, MembershipId, OrganizationId, User},
     error::Error,
     CONFIG,
 };
@@ -260,7 +260,7 @@ pub async fn send_single_org_removed_from_org(address: &str, org_name: &str) ->
 pub async fn send_invite(
     user: &User,
     org_id: Option<OrganizationId>,
-    member_id: Option<String>,
+    member_id: Option<MembershipId>,
     org_name: &str,
     invited_by_email: Option<String>,
 ) -> EmptyResult {