This report looks at and identifies emerging trends in the roles that teacher unions play in educational reform and improving the quality of teaching. A description of the efforts of six teacher unions to improve teacher quality within the context of the current systemic reform movement shows a range and depth of union initiatives beyond what is commonly known in policy research. The report highlights organizational strengths of teacher unions, the unique contributions they make to teacher quality, and some of the challenges they face. Two broad conceptions of systemic reform in support of improving teaching quality--triage and tapestry--are presented and contrasted. When educational improvement is understood as a "tapestry" of efforts that requires multiple initiatives in many arenas by many reform players, unions appear to perform several important and unique functions toward improving teacher quality. (Contains 2 tables.)