One-fourth of the adult population of Colombia is estimated to have hypertension. However, there has been relatively little attention to participatory approaches that address the social determinants of hypertension at the local level in Colombia. Early stages of a coalition for addressing hypertension in Quibdó (Colombia) included a stakeholder analysis and engagement of local organizations. This was followed by defining mutual goals, agreement of rules for decision making, and refining a shared vision. Based on a unified understanding of factors influencing hypertension risk, 12 organizations joined the local coalition. They developed an action plan for preventing hypertension and eliminating social disparities in its distribution. Lessons learned during this process suggest that, in marginalized urban areas of middle- and low-income countries, particular attention should be paid, at early implementation stages of coalition, to context specific challenges and opportunities, coalition membership and structure, reframing health, and strengthening capacity.