This paper describes the features of extensive families in Colombia, such as their size compared with other family forms. It shows that these features are related to the social conditions of the country, since the structure and dynamics of extensive families enables them to cope with the demands of life conditions and social circumstances. Four types of extensive families are described according to the main function they fulfill for their members and to the reasons determining their actual shape: a. homes that mitigate the impact of poverty and economic crisis; b. homes that become a refuge for unwedded mothers or young women separated from their spouses; c. those that require the extensive size for securing an income; and d. those that offer a life option and protection for the elderly. The intergenerational conflicts of this type of home are analyzed. Finally, the features of the extensive family are related to the findings of other research projects conducted in Colombia and elsewhere in Latin America.