This literature review focuses on managerial shared leadership inthe education sector, commonly conceptualized as co-principalship.School principals’ difficult work situation, in combination withschool leadership being significant for students’ learning, call fororganizational solutions where co-principalship can be a part. Thisreview aims to deepen knowledge about co-principalship by focusingon its antecedents and constellation-level outcomes, and theirrelationship to trust in co-principalship. A secondary aim is todiscuss the role of trust theory in empirical co-principalship studies.The promotion of antecedent conditions was found significant forthe success of co-principalship. Three types of antecedent wereidentified: organization-level antecedents, antecedents in relationto staff and others, and constellation-level antecedents. A numberof advantages were reported for the sharing principals themselves,including reduced workload and improved work-life balance. Theconstellation level is where the principals in their interaction continuouslybuild trust, and where either trust or distrust are produced.A variety of both positive and negative outcomes werereported. The empirical literature reviewed was shallow in termsof understanding trust beyond that it is critical for success in coprincipalship.Theory-based studies are suggested as a way todeepen understanding of trust content and development withregards to co-principalship.