In order to properly assess patients with primary headache, one needs to follow the cases up longitudinally. In Brazil, there were no studies using this methodology published after the publication of the latest issue of the International Classification of Headaches in 2004 -ICHD-2. This is especially important when we consider that it was only after such publication that we had the criteria used to classify some types of headaches which evolve with daily, or almost daily, spells, and which are very common in tertiary health care centers. Objective: To assess the frequency of headache types in a tertiary health care center, in a longitudinal fashion. Method: We assessed 95 consecutive patients. These patients were diagnosed and classified according to the ICDH-2. The subjects were followed up for 18 months, they were treated and reassessed. Houve estabilidade diagnóstica da migrânea. Por outro lado, a intervenção terapêutica permitiu a redução da frequência dos casos de cefaléia por uso excessivo de analgésicos, embora a frequência de cefaléia crônica diária mostrou-se praticamente inalterada. Palavras-chave: cefaléia, migrânea, diagnóstico.