As current software systems evolve continuously, both the application and its user interface (UI) have to be adapted. However, UI code is often scattered through and entangled with the application code. In large and complex UIs, this tangling renders the implementation complex and hard to maintain. The Deuce framework (Declarative User Interface Concerns Extrication) intends to reduce the complexity of UI implementations by applying separation of concerns on three UI concerns: presentation logic, business and data logic, and connection logic. It does so by using a declarative meta-language (SOUL) on top of an object oriented language (Smalltalk) such that an adequate language is provided to describe the entire structure and behavior of the UI, as well as linking it with the application.