For decades, Smalltalk has been known as the only pure object-oriented language. Since entering its modern form as Smalltalk-80 and its release by Xerox, it has become widely used for prototyping and, lately, commercial programming. Smalltalk's appeal comes primarily from its simplicity and the highly interactive development environment. Smalltalk has had little or no success in mainstream applications development primarily because it produces very large and slow applications.

Objective-C was developed as a cross between C and Smalltalk. It combines the low-level data types and efficiency of C with the high-level object system of Smalltalk. This combination produced a surprisingly useful language, but ultimately it was defeated in the marketplace by C++, probably because Objective-C is proprietary.

C++ has become surprisingly popular among mainstream applications developers. The combination of familiar C concepts and a fundamental efficiency have proven to be a very powerful draw. Unfortunately, C++ is the most complex language in common use, both in its syntax and its semantics. Experts commonly warn against using many of C++s features because of the likelihood of programmer error. While C++s object-oriented concepts and strong type system are an improvement over C, the complexity introduced by these features has driven many programmers to look for an alternative.

Dylan's goal is to combine the purity of Smalltalk with the efficiency of C++, using compilation techniques developed by the Lisp community. The result is a language which is easy to use, supports very strong object-oriented structuring, and produces small and fast applications.