Continuous Professional Development (CPD) programmes and especially coherent leader and leadership development programmes and policies have been at the centre of educational planning worldwide. The benefits for schools, staff, and pupils arising from professional development activities have been well researched into and elaborated on extensively. However, this is not the case in all educational settings. The purpose of this paper is to evaluate the impact of leadership development programmes and at the same time to address the challenges for leader and leadership development in connection to the design and delivery of relevant CPD programmes. The study adopted a coherent methodological framework for evaluating professional development programmes that builds on Guskey's (2000) and Stake's (1967) models for evaluating CPD programmes and a sound methodology for analysing evaluation data (Rasch methodology). We discuss the implications of our findings (a) for the local contextual practices in Cyprus, (b) for designing leader and leadership development programmes, and (c) for evaluation studies of relevant CPD programmes. (Contains 5 notes, 9 tables, and 4 figures.)