This paper provides a comprehensive review of the World Bank–supported Teacher Education Improvement Project for Grades 1-4 Class Teachers in the West Bank and Gaza (2008-19) and has important policy implications for similar initiatives in other developing economies. A professional development index of teaching competences was created and used to redesign, develop, implement, and evaluate pre-service and in-service programs in line with international good practice. By linking pre-service to in-service, the index is innovative in capturing the continuum of a teacher's professional development. The index as well as all elements of the pre-service and in-service programs were developed by Palestinians with consultant assistance. This developmental process strengthened the capacity of those involved and ensured understanding and ownership of outputs. The project resulted in an increase of fully qualified teachers from 54 percent in 2011 to 92 percent in 2018. In 2019, five of six university pre-service programs were granted unconditional accreditation by representative panels chaired by international experts. The project won the United Kingdom's prestigious Times Higher Education Award for International Impact, 2018 due to its innovative approaches and potential for replication in other countries. The model of reform developed in the project is currently influencing the development of strategies for the coherent and systemic reform of teacher education in World Bank–supported projects in The Gambia and Zambia.