Rapid deterioration of marine habitats and biodiversity under cumulative stressors have led to increased efforts to rebuild marine life. Yet, successes of such endeavors do not have prominent visibility in recent assessments, although these examples are particularly needed in guiding future actions to achieve our shared aspiration of a healthy ocean. Here, we provide a comprehensive assessment of 217 verified marine conservation successes across the world’s oceans and the main traits involved. Our findings reveal a balanced geography of success across the world’s oceans and that human stewardship is essential for driving conservation success, especially when different stakeholders work together in rebuilding marine life. This assessment should inform future actions and build confidence that reversing the trajectory of loss towards repairing ocean health is feasible. It also provides a basis for a “learning by doing” approach in guiding conservation success through an understanding of the levers for success versus failure.