This chapter examines developments surrounding and within Spain’s parliament, the Cortes Generales, since Spain’s transition to democracy in the mid-1970s. It provides an overview of the historical context and redemocratisation and characterises Spain’s ascension to the European Union and economic transformation. Subsequently, it analyses the formal parliamentary institutions, including asymmetric bicameralism with greater power concentrated in the lower house; party dominance; and relative weakness vis-à-vis the government—all of which have endured over time. It then traces the significant changes in the party system and the patterns of governance, particularly related to minority and majority cabinets. Finally, it reviews the establishment of regional parliaments and political decentralisation, which dispersed policy-making authority.