Religious beliefs and leadership can play important if complex roles in family planning decisions at many levels, but there are significant gaps in understanding how these influences affect family planning policies and programs. The World Faiths Development Dialogue (WFDD), in partnership with the Senegalese association CRSD (Cadre des Religieux pour la Santé et le Développement), is working to deepen understanding of how religious leadership can support Senegal’s family planning strategies. Senegal’s religious institutions affect daily life in many ways and religiosity there ranks among the world’s highest. However, specific information on how that striking statistic translates into personal decision-making is sparse. This brief reports on 2016 and 2017 studies focused on the influence of religious institutions, beliefs, and leaders on family planning decisions in Senegal.