| IAssignFieldReceiver | Interface for receiving field information when a Serializable type is assigned to a field under NodeBehaviour | 
| IComponentProcessor | Interface for Editor processing such as Undo. Used with ComponentUtility. | 
| IDataSlot | The interface of the slot that connects to the data flow | 
| IFlexibleField | FlexibleField interface | 
| IInputSlot | Interface of input DataSlot. | 
| INodeBehaviourContainer | Interface to use if Node is a NodeBehaviour container | 
| INodeBehaviourSerializationCallbackReceiver | Interface to receive callbacks upon serialization and deserialization. | 
| INodeGraphContainer | Interface to use if NodeBehaviour is a NodeGraph container | 
| IOutputSlot | Interface of output DataSlot. | 
| IOutputSlotAny | Interface that defines an output slot of any type | 
| IOverrideConstraint | Interface overriding type constraints | 
| ISerializeVersionCallbackReceiver | Callback receiver called from SerializeVersion class | 
| ISubGraphBehaviour | Interface to use if NodeBehaviour is a NodeGraph container |