diff --git a/modules/restapi/src/main/resources/docspell-openapi.yml b/modules/restapi/src/main/resources/docspell-openapi.yml
index df434dc6..da318274 100644
--- a/modules/restapi/src/main/resources/docspell-openapi.yml
+++ b/modules/restapi/src/main/resources/docspell-openapi.yml
@@ -795,6 +795,139 @@ paths:
             application/json:
               schema:
                 $ref: "#/components/schemas/BasicResult"
+  /sec/space:
+    get:
+      tags: [ Space ]
+      summary: Get a list of spaces.
+      description: |
+        Return a list of spaces for the current collective.
+
+        All spaces are returned, including those not owned by the
+        current user.
+
+        It is possible to restrict the results by a substring match of
+        the name.
+      security:
+        - authTokenHeader: []
+      parameters:
+        - $ref: "#/components/parameters/q"
+      responses:
+        200:
+          description: Ok
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/SpaceList"
+    post:
+      tags: [ Space ]
+      summary: Create a new space
+      description: |
+        Create a new space owned by the current user. If a space with
+        the same name already exists, an error is thrown.
+      security:
+        - authTokenHeader: []
+      requestBody:
+        content:
+          application/json:
+            schema:
+              $ref: "#/components/schemas/NewSpace"
+      responses:
+        200:
+          description: Ok
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/BasicResult"
+  /sec/space/{id}:
+    get:
+      tags: [ Space ]
+      summary: Get space details.
+      description: |
+        Return details about a space.
+      security:
+        - authTokenHeader: []
+      parameters:
+        - $ref: "#/components/parameters/id"
+      responses:
+        200:
+          description: Ok
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/SpaceDetail"
+    put:
+      tags: [ Space ]
+      summary: Change the name of a space
+      description: |
+        Changes the name of a space. The new name must not exists.
+      security:
+        - authTokenHeader: []
+      parameters:
+        - $ref: "#/components/parameters/id"
+      requestBody:
+        content:
+          application/json:
+            schema:
+              $ref: "#/components/schemas/NewSpace"
+      responses:
+        200:
+          description: Ok
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/BasicResult"
+    delete:
+      tags: [ Space ]
+      summary: Delete a space by its id.
+      description: |
+        Deletes a space.
+      security:
+        - authTokenHeader: []
+      parameters:
+        - $ref: "#/components/parameters/id"
+      responses:
+        200:
+          description: Ok
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/BasicResult"
+  /sec/space/{id}/member/{userId}:
+    put:
+      tags: [ Space ]
+      summary: Add a member to this space
+      description: |
+        Adds a member to this space (identified by `id`).
+      security:
+        - authTokenHeader: []
+      parameters:
+        - $ref: "#/components/parameters/id"
+        - $ref: "#/components/parameters/userId"
+      responses:
+        200:
+          description: Ok
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/BasicResult"
+    delete:
+      tags: [ Space ]
+      summary: Removes a member from this space.
+      description: |
+        Removes a member from this space.
+      security:
+        - authTokenHeader: []
+      parameters:
+        - $ref: "#/components/parameters/id"
+        - $ref: "#/components/parameters/userId"
+      responses:
+        200:
+          description: Ok
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/BasicResult"
+
   /sec/collective:
     get:
       tags: [ Collective ]
@@ -2358,6 +2491,80 @@ paths:
 
 components:
   schemas:
+    SpaceList:
+      description: |
+        A list of spaces with their member counts.
+      required:
+        - items
+      properties:
+        items:
+          type: array
+          items:
+            $ref: "#/components/schemas/SpaceItem"
+    SpaceItem:
+      description: |
+        An item in a space list.
+      required:
+        - id
+        - name
+        - owner
+        - created
+        - members
+      properties:
+        id:
+          type: string
+          format: ident
+        name:
+          type: string
+        owner:
+          $ref: "#/components/schemas/IdName"
+        created:
+          type: integer
+          format: date-time
+        members:
+          type: integer
+          format: int32
+    NewSpace:
+      description: |
+        Data required to create a new space.
+      required:
+        - name
+      properties:
+        name:
+          type: string
+    SpaceDetail:
+      description: |
+        Details about a space.
+      required:
+        - id
+        - name
+        - owner
+        - created
+        - members
+      properties:
+        id:
+          type: string
+          format: ident
+        name:
+          type: string
+        owner:
+          $ref: "#/components/schemas/IdName"
+        created:
+          type: integer
+          format: date-time
+        members:
+          type: array
+          items:
+            $ref: "#/components/schemas/IdName"
+    SpaceMember:
+      description: |
+        Information to add or remove a space member.
+      required:
+        - userId
+      properties:
+        userId:
+          type: string
+          format: ident
     ItemFtsSearch:
       description: |
         Query description for a full-text only search.
@@ -3739,6 +3946,13 @@ components:
       required: true
       schema:
         type: string
+    userId:
+      name: userId
+      in: path
+      description: An identifier
+      required: true
+      schema:
+        type: string
     itemId:
       name: itemId
       in: path
diff --git a/modules/store/src/main/resources/db/migration/postgresql/V1.8.0__spaces.sql b/modules/store/src/main/resources/db/migration/postgresql/V1.8.0__spaces.sql
index e3741345..8a43c097 100644
--- a/modules/store/src/main/resources/db/migration/postgresql/V1.8.0__spaces.sql
+++ b/modules/store/src/main/resources/db/migration/postgresql/V1.8.0__spaces.sql
@@ -19,12 +19,5 @@ CREATE TABLE "space_member" (
   foreign key ("user_id") references "user_"("uid")
 );
 
-CREATE TABLE "space_item" (
-  "id" varchar(254) not null primary key,
-  "space_id" varchar(254) not null,
-  "item_id" varchar(254) not null,
-  "created" timestamp not null,
-  unique ("space_id", "item_id"),
-  foreign key ("space_id") references "space"("id"),
-  foreign key ("item_id") references "item"("itemid")
-);
+ALTER TABLE "item"
+ADD COLUMN "space_id" varchar(254) NULL;
diff --git a/modules/store/src/main/scala/docspell/store/records/RItem.scala b/modules/store/src/main/scala/docspell/store/records/RItem.scala
index 987a77c0..3e319ffa 100644
--- a/modules/store/src/main/scala/docspell/store/records/RItem.scala
+++ b/modules/store/src/main/scala/docspell/store/records/RItem.scala
@@ -27,7 +27,8 @@ case class RItem(
     dueDate: Option[Timestamp],
     created: Timestamp,
     updated: Timestamp,
-    notes: Option[String]
+    notes: Option[String],
+    spaceId: Option[Ident]
 ) {}
 
 object RItem {
@@ -58,6 +59,7 @@ object RItem {
       None,
       now,
       now,
+      None,
       None
     )
 
@@ -80,6 +82,7 @@ object RItem {
     val created       = Column("created")
     val updated       = Column("updated")
     val notes         = Column("notes")
+    val space         = Column("space_id")
     val all = List(
       id,
       cid,
@@ -96,7 +99,8 @@ object RItem {
       dueDate,
       created,
       updated,
-      notes
+      notes,
+      space
     )
   }
   import Columns._
@@ -107,7 +111,7 @@ object RItem {
       all,
       fr"${v.id},${v.cid},${v.name},${v.itemDate},${v.source},${v.direction},${v.state}," ++
         fr"${v.corrOrg},${v.corrPerson},${v.concPerson},${v.concEquipment},${v.inReplyTo},${v.dueDate}," ++
-        fr"${v.created},${v.updated},${v.notes}"
+        fr"${v.created},${v.updated},${v.notes},${v.spaceId}"
     ).update.run
 
   def getCollective(itemId: Ident): ConnectionIO[Option[Ident]] =
diff --git a/modules/store/src/main/scala/docspell/store/records/RSpace.scala b/modules/store/src/main/scala/docspell/store/records/RSpace.scala
index d6efe2c6..1da2ef0d 100644
--- a/modules/store/src/main/scala/docspell/store/records/RSpace.scala
+++ b/modules/store/src/main/scala/docspell/store/records/RSpace.scala
@@ -1,5 +1,7 @@
 package docspell.store.records
 
+import cats.effect._
+import cats.implicits._
 import docspell.common._
 import docspell.store.impl.Column
 import docspell.store.impl.Implicits._
@@ -17,6 +19,12 @@ case class RSpace(
 
 object RSpace {
 
+  def newSpace[F[_]: Sync](name: String, account: AccountId): F[RSpace] =
+    for {
+      nId <- Ident.randomId[F]
+      now <- Timestamp.current[F]
+    } yield RSpace(nId, name, account.collective, account.user, now)
+
   val table = fr"space"
 
   object Columns {
@@ -41,4 +49,35 @@ object RSpace {
     sql.update.run
   }
 
+  def update(v: RSpace): ConnectionIO[Int] =
+    updateRow(
+      table,
+      and(id.is(v.id), collective.is(v.collectiveId), owner.is(v.owner)),
+      name.setTo(v.name)
+    ).update.run
+
+  def existsByName(coll: Ident, spaceName: String): ConnectionIO[Boolean] =
+    selectCount(id, table, and(collective.is(coll), name.is(spaceName)))
+      .query[Int]
+      .unique
+      .map(_ > 0)
+
+  def findById(spaceId: Ident): ConnectionIO[Option[RSpace]] = {
+    val sql = selectSimple(all, table, id.is(spaceId))
+    sql.query[RSpace].option
+  }
+
+  def findAll(
+      coll: Ident,
+      nameQ: Option[String],
+      order: Columns.type => Column
+  ): ConnectionIO[Vector[RSpace]] = {
+    val q = Seq(collective.is(coll)) ++ (nameQ match {
+      case Some(str) => Seq(name.lowerLike(s"%${str.toLowerCase}%"))
+      case None      => Seq.empty
+    })
+    val sql = selectSimple(all, table, and(q)) ++ orderBy(order(Columns).f)
+    sql.query[RSpace].to[Vector]
+  }
+
 }
diff --git a/modules/store/src/main/scala/docspell/store/records/RSpaceItem.scala b/modules/store/src/main/scala/docspell/store/records/RSpaceItem.scala
deleted file mode 100644
index ab7187fd..00000000
--- a/modules/store/src/main/scala/docspell/store/records/RSpaceItem.scala
+++ /dev/null
@@ -1,42 +0,0 @@
-package docspell.store.records
-
-import docspell.common._
-import docspell.store.impl.Column
-import docspell.store.impl.Implicits._
-
-import doobie._
-import doobie.implicits._
-
-case class RSpaceItem(
-    id: Ident,
-    spaceId: Ident,
-    itemId: Ident,
-    created: Timestamp
-)
-
-object RSpaceItem {
-
-  val table = fr"space"
-
-  object Columns {
-
-    val id      = Column("id")
-    val space   = Column("space_id")
-    val item    = Column("user_id")
-    val created = Column("created")
-
-    val all = List(id, space, user, created)
-  }
-
-  import Columns._
-
-  def insert(value: RSpaceItem): ConnectionIO[Int] = {
-    val sql = insertRow(
-      table,
-      all,
-      fr"${value.id},${value.spaceId},${value.itemId},${value.created}"
-    )
-    sql.update.run
-  }
-
-}