Abstract COVID‐19 has highlighted worldwide the importance of a strong social and political fabric. Those countries that fared best were ones where there was community connection, belonging, a volunteering ethos, and a belief in the legitimacy of official institutions, all deemed critical aspects of social cohesion. It has become clear that understanding and strengthening social cohesion in times of stability is critical to successfully navigate crisis. Despite its importance, evidence from many countries indicates that this important “social glue” is fragile and at risk, requiring consistent investments to maintain and strengthen it. Governments and communities around the world are looking to evidence‐based strategies to strengthen social cohesion. To facilitate this goal, a systematic review is conducted of four major databases identifying 52 studies with high‐quality evidence of what works and why. We also included the results of three systematic reviews that had investigated the impact of social capital and/or social cohesion on health‐related variables specifically to broaden our search and enrich our findings ( n  = 21; total = 73). Using themes identified across governments, it is possible to classify the strengths and limitations of existing research. It becomes clear that the most common effective strategies were (1) awareness raising and coutering existing stereotypes and (2) offering opportunities for positive contact and a more co‐operative assessment of intergroup relations. Missing are leadership processes that can (re)define group‐based values, norms, and behaviors. Specific intervention strategies are outlined as well as directions for future research.