The Anuário Regional de Lisboa e Vale do Tejo (Regional Yearbook of the Lisboa and Vale do Tejo Region), which is published since 1993, is already a reference publication in the supply of regional and especially infra-regional statistical data. The municipality is the main geographical breakdown. Albeit subject to the data availability constraints of the national statistical system, the main purpose of this publication is to cope with the growing demand for infra-regional information in various thematic areas (population, economic activity, environment, etc.), in the wake of the need to understand the socio-economic reality of these territories.