The Colombian reform to the health system (Law 100 of 1993) established, as strategy to facilitate the access, the universality of a health insurance that is acquired by means of the quotation in the contributive regime or by means of the gratuitous affiliation to the subsidized regime, in order to cover all the population with a unique plan of benefits that includes services in all levels of complexity. In this paper we intend to cover the main streamlined facts of the reform as far as coverage and access of the insurance, by means of logit models, the determinants of the enrollment and the access are considered, using data from the Living Standards Surveys of 1997 and 2003. It stands out that the coverage rose from 20% of the population in 1993 to 60% in 2003, although it seems very difficult to reach the universality; the structure and evolution of the coverage show that both regimes complement each other, while the contributive one has greater presence in the cities and among the population with formal employment, the subsidized one has greater weight among the rural population and in those with low levels of income; on the other hand, the insurance has advantages for the subsidized population, with a greater probability for use of the services, although the plan offers less benefits than the contributive one there are some barriers for the access.
