Wastewater pollution is a serious problem in the Caribbean. The Nature Conservancy (TNC) is assessing wastewater management in four island nations—the Dominican Republic, Haiti, Jamaica, and Grenada—to understand the barriers and opportunities for addressing this issue. The assessment focuses on scientific/technological approaches; policy, legal, and institutional frameworks; and stakeholder engagement. This analysis attempts to focus on findings specific to NBS as a wastewater treatment approach from more engineered or “grey” solutions.