To complement studies on design sketching within particular phases of design processes in specific design domains, this paper analyzes descriptions of design processes given by designers from a wide variety of fields. This research forms part of a wider project on comparisons across design domains and draws attention to the many types and properties of sketches in different contexts. Further, it focuses on the multiple roles that sketching can take in idea generation, as well as in reasoning and communicating design ideas. In particular this paper examines how the different types and roles of sketches can be more or less formal and how this can lead to misunderstandings.