This article analyses the degree to which diffusion of Portugal's semi-presidential constitution occurred within lusophone countries following their move to multipartism in the 1990s. To do so, we first identify the main characteristics of the 1976 Portuguese constitution. Next, the constitutional choices made in Angola, Cape Verde, Guinea-Bissau, Mozambique, Sao Tome and Principe, and East Timor are mapped. Using existing typologies, we classify these regimes and contrast them with their European and francophone African counterparts. Finally, we investigate the effective dynamics of lusophone semi-presidential systems by focusing on how heads of state deal with heads of government and parliamentary majorities. We claim there is a "family resemblance" among lusophone semi-presidential regimes. This finding is important because it accounts for constitutional choices in a group of recent democratizing countries, and shows how external influences interact with local factors to produce major political outcomes.