"Teachers Teaching Teachers" ("T3") focuses on coaches' roles in the professional development of teachers. Each issue also explores the challenges and rewards that teacher leaders encounter. This issue includes: (1) Sharpening Skills for Our Century (Valerie von Frank); (2) Lessons from a Coach: First, I Assess How Teachers Learn (Julie McDonnell); (3) Focus on NSDC's [National Staff Development Council's] Standards: Collaboration Needs Resolution Skills (Joellen Killion); and (4) NSDC Tool: Trust Factors. [For Volume 5, Number 1 of "Teachers Teaching Teachers," see ED507657.]