This report, in two volumes, describes an investigation of the links between teacher professional development and student learning outcomes. The study, funded by the Australian Government, provides a review of the research literature and of national and international initiatives linking professional development with student outcomes. It provides detailed case studies of the school-based trials of ten professional development programs in a number of different sites. It examines the repeated measures of student achievement from students in the classes of teachers in the school-based trials. Analysis and discussion of a common questionnaire completed by teachers in the school-based trials is provided. Suggestions are made for a method that could be used by the Australian Government to assess the impact of professional development programs.