diff --git a/essentials-framework/Essentials Core/PepperDashEssentialsBase/PartitionSensor/IPartitionStateProvider.cs b/essentials-framework/Essentials Core/PepperDashEssentialsBase/PartitionSensor/IPartitionStateProvider.cs
index 0080e472..08b8012b 100644
--- a/essentials-framework/Essentials Core/PepperDashEssentialsBase/PartitionSensor/IPartitionStateProvider.cs	
+++ b/essentials-framework/Essentials Core/PepperDashEssentialsBase/PartitionSensor/IPartitionStateProvider.cs	
@@ -4,13 +4,24 @@ using System.Linq;
 using System.Text;
 using Crestron.SimplSharp;
 
+using PepperDash.Core;
+
 namespace PepperDash.Essentials.Core
 {
     /// <summary>
     /// Describes the functionality of a device that senses and provides partition state
     /// </summary>
-    public interface IPartitionStateProvider
+    public interface IPartitionStateProvider : IKeyName
     {
         BoolFeedback PartitionSensedFeedback { get; }
     }
+
+    public interface IManualPartitionSensor : IPartitionStateProvider
+    {
+        void SetPartitionStatePresent();
+
+        void SetPartitionStateNotPresent();
+
+        void ToggglePartitionState();
+    }
 }
\ No newline at end of file
diff --git a/essentials-framework/Essentials Core/PepperDashEssentialsBase/PepperDash_Essentials_Core.csproj b/essentials-framework/Essentials Core/PepperDashEssentialsBase/PepperDash_Essentials_Core.csproj
index 7e18606f..b65cfd62 100644
--- a/essentials-framework/Essentials Core/PepperDashEssentialsBase/PepperDash_Essentials_Core.csproj	
+++ b/essentials-framework/Essentials Core/PepperDashEssentialsBase/PepperDash_Essentials_Core.csproj	
@@ -289,6 +289,8 @@
     <Compile Include="Remotes\Hrxx0WirelessRemoteController.cs" />
     <Compile Include="Room\Behaviours\RoomOnToDefaultSourceWhenOccupied.cs" />
     <Compile Include="Room\Combining\EssentialsRoomCombinerPropertiesConfig.cs" />
+    <Compile Include="Room\Combining\IEssentialsRoomCombiner.cs" />
+    <Compile Include="Room\Combining\RoomCombinationScenario.cs" />
     <Compile Include="Room\EssentialsRoomBase.cs" />
     <Compile Include="Room\Config\EssentialsRoomScheduledEventsConfig.cs" />
     <Compile Include="Room\IEssentialsRoom.cs" />
diff --git a/essentials-framework/Essentials Core/PepperDashEssentialsBase/Room/Combining/EssentialsRoomCombinerPropertiesConfig.cs b/essentials-framework/Essentials Core/PepperDashEssentialsBase/Room/Combining/EssentialsRoomCombinerPropertiesConfig.cs
index 5f1adcfa..74d5ebda 100644
--- a/essentials-framework/Essentials Core/PepperDashEssentialsBase/Room/Combining/EssentialsRoomCombinerPropertiesConfig.cs	
+++ b/essentials-framework/Essentials Core/PepperDashEssentialsBase/Room/Combining/EssentialsRoomCombinerPropertiesConfig.cs	
@@ -8,21 +8,30 @@ using PepperDash.Core;
 
 using Newtonsoft.Json;
 
-namespace PepperDash.Essentials.Core.Room
+namespace PepperDash.Essentials.Core
 {
     /// <summary>
     /// Config properties for an EssentialsRoomCombiner device
     /// </summary>
     public class EssentialsRoomCombinerPropertiesConfig
     {
+        /// <summary>
+        /// The list of partitions that device the rooms
+        /// </summary>
         [JsonProperty("partitions")]
         public List<PartitionConfig> Partitions {get; set;}
 
+        /// <summary>
+        /// The list of combinations scenarios for the rooms
+        /// </summary>
         [JsonProperty("scenarios")]
-        public List<RoomCombinationScenario> Scenarios { get; set; }
+        public List<RoomCombinationScenarioConfig> Scenarios { get; set; }
 
-        [JsonProperty("rooms")]
-        public List<IKeyed> Rooms {get; set;}
+        /// <summary>
+        /// The list of rooms that can be combined
+        /// </summary>
+        [JsonProperty("roomMap")]
+        public Dictionary<string, string> RoomMap {get; set;}
     }
 
     /// <summary>
@@ -46,7 +55,7 @@ namespace PepperDash.Essentials.Core.Room
     /// <summary>
     /// Config propeties for a room combination scenario
     /// </summary>
-    public class RoomCombinationScenario : IKeyName
+    public class RoomCombinationScenarioConfig : IKeyName
     {
         [JsonProperty("partitionStates")]
         public List<PartitionState> PartitionStates { get; set; }
@@ -67,6 +76,6 @@ namespace PepperDash.Essentials.Core.Room
         public string PartitionKey { get; set; }
 
         [JsonProperty("partitionSensedState")]
-        public bool PartitionSensedState { get; set; }
+        public bool PartitionPresent { get; set; }
     }
 }
\ No newline at end of file
diff --git a/essentials-framework/Essentials Core/PepperDashEssentialsBase/Room/Combining/IEssentialsRoomCombiner.cs b/essentials-framework/Essentials Core/PepperDashEssentialsBase/Room/Combining/IEssentialsRoomCombiner.cs
new file mode 100644
index 00000000..894dd098
--- /dev/null
+++ b/essentials-framework/Essentials Core/PepperDashEssentialsBase/Room/Combining/IEssentialsRoomCombiner.cs	
@@ -0,0 +1,41 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using Crestron.SimplSharp;
+
+using PepperDash.Core;
+
+namespace PepperDash.Essentials.Core
+{
+    /// <summary>
+    /// Describes the functionality for an EssentailsRoomCombiner device
+    /// </summary>
+    public interface IEssentialsRoomCombiner
+    {
+        // TODO: Update the EventArgs class as needed to specify scenario change
+        event EventHandler<EventArgs> RoomCombinationScenarioChanged;
+
+        BoolFeedback IsInAutoModeFeedback {get;}
+
+        void SetAutoMode();
+
+        void SetManualMode();
+
+        void ToggleMode();
+
+        List<IRoomCombinationScenario> Scenarios { get; }
+
+        List<IPartitionStateProvider> Partitions { get; }
+
+        void TogglePartitionState(string partitionKey);
+    }
+
+    public interface IRoomCombinationScenario : IKeyName
+    {
+        BoolFeedback IsActive { get; }
+
+        void Activate();
+    }
+
+}
\ No newline at end of file
diff --git a/essentials-framework/Essentials Core/PepperDashEssentialsBase/Room/Combining/RoomCombinationScenario.cs b/essentials-framework/Essentials Core/PepperDashEssentialsBase/Room/Combining/RoomCombinationScenario.cs
new file mode 100644
index 00000000..965428cb
--- /dev/null
+++ b/essentials-framework/Essentials Core/PepperDashEssentialsBase/Room/Combining/RoomCombinationScenario.cs	
@@ -0,0 +1,17 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using Crestron.SimplSharp;
+
+namespace PepperDash.Essentials.Core
+{
+    /// <summary>
+    /// Represents a room combination scenario
+    /// </summary>
+    public class RoomCombinationScenario: IRoomCombinationScenario
+    {
+
+    }
+
+}
\ No newline at end of file