I'm working on a research project that closely resembles a UML class diagram creation program. I started out using Java and JHotDraw to create my own figures, tools, etc, but I really would prefer to use C# as I am much more confident in the language and there are a lot of different aspects to this project which would make C# my preferred language.

Are there any drawing frameworks for C# which allow the programmer to create their own models and creation tools?