Application development and delivery (AD&D) professionals are rapidly adopting responsive web design (RWD) to solve multi-device challenges. Unfortunately, poor examples of RWD soured some digital strategists on the philosophy. As a result, some web strategists advocate for adaptive design to better embrace the user's device context. The "responsive versus adaptive" debate continues today, but Forrester outlines why these traditional definitions are limiting. This report also provides guidance on four tiers of content and the design treatments they deserve.