Uncrewed Surface Vehicles (USVs) have long promised to revolutionize ocean data acquisition, especially in remote areas. These USVs have generally fallen short of expectations due to their limited range and power, combined with the need to provide substantial support from a ground team or mother ship. Saildrone went back to a tried and true practice for renewable energy propulsion-the wind. As a result, the capability now exists to provide persistent presence for ocean observations, mapping and surveillance without the need for on-scene human support. This talk will review Saildrone, its technology and missions with special emphasis on ocean mapping.