I'm going to speak in generalities here... If you do a lot of work with polymorphism then dynamic languages tend to be a much better fit. With polymorphic desig

I'm going to speak in generalities here... If you do a lot of work with polymorphism then dynamic languages tend to be a much better fit. With polymorphic designs, you dont care what the type of your instance is, you don't care about its entire interface, you just care, does it respond to this message ( or set of messages ). I have used and continue to use both dynamically and statically typed languages and I find value in both. I do find little value in static type system that can't do type inference. As to a couple of your generalities, a tour through smalltalk would do you well if you think that excellent IDE support and great refactoring are something that springs from static typing. EDIT: People talk a good deal about the + of compile time type checking. I have done tons of coding in statically typed languages like C, C++ and more and I think the compile has caught less than a dozen type errors for me ever and those were usually because I got lost in pointer hell. Most errors that a compiler would catch because of type has been in my experience something that there should be a unit test for and the unit test would have caught.