Abstract. This paper provides an overview of the trends of the Spanish solar PV feed-in tariff (FIT) and its design elements, identifies some implications for the effective and cost-efficient deployment of solar PV in Spain and infers some lessons which might be useful for the implementation of support for solar PV elsewhere. Our analysis is based on a throughout revision of the relevant legislation, official data on deployment and related expenditure, informal discussions with key stakeholders and written documents. Several key design elements within FITs that should be implemented and other elements that should be avoided in order to have an effective and cost-efficient promotion of solar PV are identified. All in all, the specific design elements to be included are clearly contingent upon the preferences and priorities of policymakers.