Portugal has evolved through different political and institutional regimes during the twentieth century. The parliamentary regime existing at the beginning of the century was substituted by an authoritarian one in the late 1920s, as a result of the political and economic turmoil resulting from the post-war monetary and financial crises. For almost 50 years this new regime favored strong, but indirect, state intervention, creating a complex web of institutions based on industrial conditioning, which limited the entry of firms in the various industrial markets and supported the creation of oligopolistic or monopolistic markets, and corporatism, which generated a cartelized and highly controlled economy in some sectors. Some business groups prospered in this specific context, particularly after the mid-twentieth century. The period from 1950 to 1973 was also the Portuguese version of the "golden age of European growth" after World War Two. Eventually, in 1974 the authoritarian regime was overthrown, giving rise to a new type of state intervention in the economy, through the creation of multiple state-owned enterprises in several important economic sectors (finance, transport, heavy industry...). Only after the late 1980s state-owned enterprises started to be privatized, a trend that accelerated in the 1990s.

This paper provides a first insight on the evolution of corporate networks over the twentieth century. The chosen benchmarks (1917, 1925, 1937, 1957, 1973, 1983 and 2003) try to cover the entire period in a meaningful way. Besides being constrained by the availability of data, the proposed benchmark years anticipate the possible impact of some contextual variables related to the regulatory and institutional framework, the role of business groups and financial institutions in creating a network of related firms, as well as the relative presence of state-owned enterprises. The reconstitution of the ties between the administrative boards' members in the top 125 firms for these cross-sectional cuts will provide an outline about the impact of different governance regimes in the corporate networks. In addition, it will provide the first attempt to integrate the Portuguese case into a European comparative perspective on the impact of institutions and structural change on corporate ties.