This article examines the significance of professional development (PD) in shaping the beliefs undergirding teachers' classroom practices specifically learner-centred and teacher-centred beliefs, ICT beliefs and use of Information and Communication Technology (ICT). It highlights key considerations for designing and implementing PD grounded in teachers' perspectives and experiences with PD in the use of ICT. It draws on findings from an explanatory sequential mixed methods study conducted with 248 Jamaican teachers. Data collection comprised a quantitative survey in phase one and multiple case studies in phase two using semi-structured interviews, classroom observations, video recording of lessons, observation checklist and video-elicitation interviews. The quantitative results revealed that PD had a significant direct effect on teachers' beliefs about teaching but was not directly related to differences in ICT beliefs and use of ICT. The case study findings revealed that content, collaboration and active learning were the most impactful during PD in shaping teachers' beliefs about teaching with ICT. However, the data revealed predominantly teacher-centred use of ICT and misconceptions in teachers' understanding of effective teaching, with ICT suggesting that PD must do more than influence teachers' beliefs because a change in beliefs does not automatically translate into changes in the use of ICT.