Purpose: The purpose of this paper is to explore successful school principalship in Cyprus based on a ten-year research project, and in particular, by analysing leadership knowledge based on concrete actions of successful school principals derived from multiple case studies from the primary and secondary education sectors in Cyprus. Design/methodology/approach: The initial type of evidence was original qualitative empirical research undertaken through the examination of 11 case studies of successful primary and secondary school principals across Cyprus. Following, for the purposes of this paper a cross-case reanalysis was performed in order to extract successful actions from the participating school principals. Findings: Based on the emerging actions from the cross-case analysis, findings indicate that successful school principals, both in primary and secondary education, develop external relations, as well as networking with all relevant actors; create a collaborative and shared ownership feeling among their members and within their school organization; and finally promote a clear vision, based on a specific number of values. Originality/value: This overall effort led us to the articulation of certain successful actions, which could be related and compared to the results in other successful school principalship contexts. Furthermore, it could contribute to the cross-country comparative knowledge body on successful school principalship, with different educational policies and different social contexts.