Although information and communication technology (ICT) has gradually become a standard teaching technology in schools in many countries and regions like Hong Kong, the implementation of ICT in teaching and learning in schools still fails to meet high government and public expectations. This study was an investigation into the potential of peer support to enhance professional development of ICT integration for secondary school teachers in Hong Kong. The study utilized peer support as a social approach to professional development and employed action research to examine the experiences of ten secondary school teachers who worked in five peer support groups for sixteen months. A peer support model was introduced to the participants who then applied these principles in their own contexts. Data on participants' reflections and evaluations of the peer support process was collected through individual interviews and peer-group conferences. Each participant was interviewed at the beginning, middle and end of the research period and each peer group was interviewed at the end of the project. By employing a grounded theory approach, themes related to the participants' experiences of peer support for ICT integration and the impact of peer support as a means of professional development were generated from the data. The study's findings indicate that the participants responded positively to peer support as a means of professional development. Peer support was successful in: increasing professional interactions; broadening perspectives of ICT; increasing reflection; and providing personal and emotional support. From an analysis of the study's findings, in conjunction with a review of the appropriate literature, a teacher professional development model for ICT integration has been developed that may be helpful in furthering the goal of successful ICT integration. This model focuses on the importance of intrinsic motivation rather than extrinsic incentives and is based on a developmental process in which individual teachers determine their own practice through peer support enhanced critical reflection that continually expands their personal context of ICT integration.