This study produced a theoretically grounded model of professional development suited for supporting teachers in Hong Kong to embed Information and Communication Technologies into the Primary School Curriculum. The model was developed and tested over two years through an intervention based on participatory action research involving school staff and the researcher as a critical friend. The model was tested through the analysis of extensive qualitative and quantitative analysis of teacher behaviours and curricular documents. Teachers' beliefs and practices were found to change significantly during the first year of the project and were further refined during the second year. Leadership, collegial support, physical infrastructure, teacher self-efficacy, and technical knowledge were identified as the most important factors underpinning the successful implementation of the program. The model addresses these factors and has considerable potential to impact on educational practice involving ICT in the Hong Kong context.