This issue of "Teachers Teaching Teachers" ("T3") focuses on coaches' role in the professional development of teachers. It contains the following articles: (1) An Excerpt from "Taking the Lead" (Joellen Killion and Cindy Harrison); (2) Be Like a Virus and Connect (Bill Ferriter); (3) No. 1 Resource Has a Human Face (Joellen Killion); (4) With This Coach, the Topic Always Turns Back to Instruction (Tracy Crow); and (5) New Math Concept? To Teach It, Show It (Carla Thomas McClure).