This chapter adopts the concept of water security as securing water for people and their livelihoods while safeguarding ecosystem services in Spain, which has a long history of engaging with water security. The chapter analyses water security from a Spanish perspective by focusing on the evolution of the concept, which has adapted over time to mirror socio-economic changes. The chapter looks at the different dimensions of water security relevant to the Spanish case: the potential impact of climate change; environmental water security through a review of the water body status determination under the EU Water Framework Directive; productive water security looking at the main issues in relation to agriculture as the dominant water consumptive sector; and finally water in human and political security, discussing allocation, transboundary aspects and regional conflicts over water.