This document discusses the benefits of sketching for product design. It argues that sketching helps designers communicate ideas visually, record what they see and hear, work through problems, and document the design process. Sketching is presented as a way to move past talking about design at an abstract level and start exploring how design ideas could work in practice. The document provides examples of how the author sketches for wireframes, presentations, and design studios with clients and users. It encourages testing early sketches with users to help validate design requirements.