In reply to @difuse_ "Hi, I'm new to": Having a plugin system generally sounds doable. Trying to override a method on an object when another DLL is loaded I struggle with imagining as a concept more generally. I think you'd have an easier time if you had an Object-factory and that instantiated different subtypes based on the loaded DLLs. I mean, even if those are methods, you'd still need to instantiate the type with those methods and then pass that one around. If that shoots you in the knee somewhere I can't predict, OOP tends to be that way when I try to anticipate how it might limit extensibility