This report establishes the methodological foundations for the design of a global synthetic index of sustainable development which fulfils three conditions: it adapts to the principles of Pressure-State-Response,it adopts the mandates established in Local Agenda 21 and adapts to the four components or basic dimensions of sustainability: institutional, environmental, economic and social.The synthetic index is constructed using the aforesaid methodology and based on the calculations of 78 variables,37 sub-indicators and 13 indicators,grouping the latter in the previously mentioned four dimensions and subsequently applying said index to the regions within Spain.