This study deals with the evolution of fertility and nuptiality patterns in the Basque Country from pre-industrial times to the present, with special emphasis on current demographic evolution. This work has intended to investigate the following questions. First, it has sought to clarify the diversity of fertility and nuptiality patterns in the Basque area during pre-industrial times in the light of new local research and to establish at demographic level the well known differences within the Basque Country between the coastal (Bizkaia and Gipuzkoa) and the interior (Araba and Nafarroa) territories. Second, it has attempted to trace the permanence of fundamental aspects of the Atlantic nuptiality model into modern society: the continuous interplay of limited access to marriage and older age at marriage in periods of limited resources, even at present, with a widespread access to modern contraceptive technology. Third, to establish that the nuptiality and fertility models are mainly culturally based so that variations in the demographic behaviour among social and economic groups are likely to be minimal. Census, Vital Registration and local level data have been used to analyse these points. The 1977 and 1985 National Fertility Surveys have been used to test the modernization and economic hypothesis on a comparative perspective. These two fertility surveys taken in Spain have provided in depth information on the socio-economic, cultural and demographic characteristics of women in the Basque Country during the current period of economic crisis, indicating the quick adaptation of a modern demographic model on the verge of stability (generalized marriage at younger ages with fast declining marital fertility trends) to a restrictive demographic behaviour based on declining marriage, older ages at marriage while experiencing further fertility declines to well below replacement levels. This analysis refers exclusively to the Peninsular side of the Basque Country, to the provinces of Araba, Bizkaia, Gipuzkoa and Nafarroa in Spain.