Malcolm Bauer, from Education Testing Services, provides his comments on the Focus article in this issue of "Measurement" entitled : "How Task Features Impact Evidence from Assessments Embedded in Simulations and Games" (Russell G. Almond, Yoon Jeon Kim, Gertrudes Velasquez, Valerie J. Shute). Bauer begins his remarks by noting that the Focus article explores a key part of evidence-centered design (ECD)--6 different but nonexclusive roles that task model variables can have and their function within an overall assessment design. The authors of the Focus article provide examples of these roles for more-conventional tasks (math word problems) and for a game-based formative assessment, "Newton's Playground." While the Focus article emphasizes structure--the roles of these variables and the relation of these variables to the rest of the assessment design, Bauer's commentary addresses aspects of ECD that are complementary to the article, specifically aspects of process (How does one create a design involving task model variables? What is the dynamic relation between the student-model, evidence-model, and task-model variables as they are developed and revised?). While the structures described in Almond et al. provide the "what" of evidence-centered assessment design, Bauer describes the intent of this commentary as more of a discussion about the design process itself-that is, the "how" that leads to these useful structures.