The Arizona Head Start--Public School Transition Project is 1 of 31 demonstration projects designed to test whether advances by Head Start children could be maintained by continuing Head Start-type services into kindergarten through the third grade, and to identify, develop, and implement transition practices to bridge the gap between Head Start and public schools. This study evaluated the Arizona project in its fourth year of implementation. Participating were two cohorts of students at three transition and three comparison schools in Phoenix. The program components evaluated were: (1) developmentally appropriate practices, curriculum, and materials; (2) physical health, mental health, and dental services; (3) family services; and (4) parent involvement. Findings indicated that all components had been implemented by the time of the 1995-96 evaluation. Both cohorts had similar public assistance participation, and all groups showed dramatic decreases in public assistance since program entry. The vast majority of parents from all groups reported positive interactions with schools; qualitative data confirmed continuing positive impact on teachers, schools, and the Head Start agency. Transition services, especially those of family advocates, were seen as crucial to smooth transitions. There were observable differences between transition and comparison classrooms; however, quantitative data showed few significant differences in gains made by children between transition and comparison classrooms. Confounding variables of high attrition, variations in student English proficiency, and the existence in comparison schools of transition-like services may have influenced the results. Promising practices and further challenges were identified and recommendations were made for improving the collaboration between the Head Start program and the public schools, and improving the evaluation process. (Three appendices include a summary of data collection instruments. Contains 20 references.)