The Collaborative, Site-Based Teacher Preparation Program in Early Childhood has transformed the way that the University of Wisconsin-Green Bay Professional Program in Education conducts early childhood teacher preparation. Preservice teachers now engage in performance-based learning in collaboratively supported, community- and public school-based early childhood settings where they learn to work with culturally, linguistically, and ability-diverse young children and their families. Course content is taught on-site or delivered through online core modules, and competency acquisition is supported by field-based faculty mentors who work closely with students and cooperating teachers. Seminars give students an opportunity to join together to critically reflect on their experiences and solve problems. Performance-based assessment tools are being developed to measure preservice teacher outcomes. Project outcomes being looked at include: (1) improved preservice student learning and teaching, (2) teachers who are prepared to work with diverse populations, (3) strengthened linkages and improved continuity between child care facilities and public schools, and (4) a teacher preparation model that can be applied at all levels of teacher education. (Contains 30 references.) (Author/HTH)