diff --git a/CHANGES.md b/CHANGES.md
index df550511e2..2c9387b456 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -7,6 +7,7 @@ Features ✨:
 
 Improvements 🙌:
  - "Add Matrix app" menu is now always visible (#1495)
+ - Handle `/op` and `/deop` commands (#12)
 
 Bugfix 🐛:
  - Fix dark theme issue on login screen (#1097)
diff --git a/vector/src/main/java/im/vector/riotx/features/command/CommandParser.kt b/vector/src/main/java/im/vector/riotx/features/command/CommandParser.kt
index e7d2e9a62b..7c32a34aff 100644
--- a/vector/src/main/java/im/vector/riotx/features/command/CommandParser.kt
+++ b/vector/src/main/java/im/vector/riotx/features/command/CommandParser.kt
@@ -232,7 +232,7 @@ object CommandParser {
                         val userId = messageParts[1]
 
                         if (MatrixPatterns.isUserId(userId)) {
-                            ParsedCommand.SetUserPowerLevel(userId, 0)
+                            ParsedCommand.SetUserPowerLevel(userId, null)
                         } else {
                             ParsedCommand.ErrorSyntax(Command.SET_USER_POWER_LEVEL)
                         }
diff --git a/vector/src/main/java/im/vector/riotx/features/command/ParsedCommand.kt b/vector/src/main/java/im/vector/riotx/features/command/ParsedCommand.kt
index 63e016b0b6..44ad2265e1 100644
--- a/vector/src/main/java/im/vector/riotx/features/command/ParsedCommand.kt
+++ b/vector/src/main/java/im/vector/riotx/features/command/ParsedCommand.kt
@@ -39,7 +39,7 @@ sealed class ParsedCommand {
     class SendRainbowEmote(val message: CharSequence) : ParsedCommand()
     class BanUser(val userId: String, val reason: String?) : ParsedCommand()
     class UnbanUser(val userId: String, val reason: String?) : ParsedCommand()
-    class SetUserPowerLevel(val userId: String, val powerLevel: Int) : ParsedCommand()
+    class SetUserPowerLevel(val userId: String, val powerLevel: Int?) : ParsedCommand()
     class Invite(val userId: String, val reason: String?) : ParsedCommand()
     class JoinRoom(val roomAlias: String, val reason: String?) : ParsedCommand()
     class PartRoom(val roomAlias: String, val reason: String?) : ParsedCommand()
diff --git a/vector/src/main/java/im/vector/riotx/features/home/room/detail/RoomDetailViewModel.kt b/vector/src/main/java/im/vector/riotx/features/home/room/detail/RoomDetailViewModel.kt
index 3e8949e94c..a0c7447569 100644
--- a/vector/src/main/java/im/vector/riotx/features/home/room/detail/RoomDetailViewModel.kt
+++ b/vector/src/main/java/im/vector/riotx/features/home/room/detail/RoomDetailViewModel.kt
@@ -41,6 +41,7 @@ import im.vector.matrix.android.api.session.file.FileService
 import im.vector.matrix.android.api.session.homeserver.HomeServerCapabilities
 import im.vector.matrix.android.api.session.room.members.roomMemberQueryParams
 import im.vector.matrix.android.api.session.room.model.Membership
+import im.vector.matrix.android.api.session.room.model.PowerLevelsContent
 import im.vector.matrix.android.api.session.room.model.RoomMemberSummary
 import im.vector.matrix.android.api.session.room.model.RoomSummary
 import im.vector.matrix.android.api.session.room.model.message.MessageContent
@@ -448,8 +449,8 @@ class RoomDetailViewModel @AssistedInject constructor(
                             popDraft()
                         }
                         is ParsedCommand.SetUserPowerLevel        -> {
-                            // TODO
-                            _viewEvents.post(RoomDetailViewEvents.SlashCommandNotImplemented)
+                            handleSetUserPowerLevel(slashCommandResult)
+                            popDraft()
                         }
                         is ParsedCommand.ClearScalarToken         -> {
                             // TODO
@@ -668,6 +669,22 @@ class RoomDetailViewModel @AssistedInject constructor(
         }
     }
 
+    private fun handleSetUserPowerLevel(setUserPowerLevel: ParsedCommand.SetUserPowerLevel) {
+        val currentPowerLevelsContent = room.getStateEvent(EventType.STATE_ROOM_POWER_LEVELS)
+                ?.content
+                ?.toModel<PowerLevelsContent>() ?: return
+
+        launchSlashCommandFlow {
+            if (setUserPowerLevel.powerLevel == null) {
+                currentPowerLevelsContent.users.remove(setUserPowerLevel.userId)
+            } else {
+                currentPowerLevelsContent.users[setUserPowerLevel.userId] = setUserPowerLevel.powerLevel
+            }
+
+            room.sendStateEvent(EventType.STATE_ROOM_POWER_LEVELS, null, currentPowerLevelsContent.toContent(), it)
+        }
+    }
+
     private fun handleKickSlashCommand(kick: ParsedCommand.KickUser) {
         launchSlashCommandFlow {
             room.kick(kick.userId, kick.reason, it)
diff --git a/vector/src/main/java/im/vector/riotx/features/roommemberprofile/RoomMemberProfileViewModel.kt b/vector/src/main/java/im/vector/riotx/features/roommemberprofile/RoomMemberProfileViewModel.kt
index aca584a663..62f77e98c9 100644
--- a/vector/src/main/java/im/vector/riotx/features/roommemberprofile/RoomMemberProfileViewModel.kt
+++ b/vector/src/main/java/im/vector/riotx/features/roommemberprofile/RoomMemberProfileViewModel.kt
@@ -162,7 +162,11 @@ class RoomMemberProfileViewModel @AssistedInject constructor(@Assisted private v
         } else if (action.askForValidation && state.isMine) {
             _viewEvents.post(RoomMemberProfileViewEvents.ShowPowerLevelDemoteWarning(action.previousValue, action.newValue))
         } else {
-            currentPowerLevelsContent.users[state.userId] = action.newValue
+            if (action.newValue == currentPowerLevelsContent.usersDefault) {
+                currentPowerLevelsContent.users.remove(state.userId)
+            } else {
+                currentPowerLevelsContent.users[state.userId] = action.newValue
+            }
             viewModelScope.launch {
                 _viewEvents.post(RoomMemberProfileViewEvents.Loading())
                 try {