Twenty-five patients underwent 33 stereotactic procedures on the thalamus for the treatment of persistent pain of benign or malignant origin. There were 19 ablative and 14 stimulation procedures. The thalamic targets were the centrum medianum (CM), the pulvinar, the nucleus ventralis posteromedialis and/or the nucleus ventralis posterolateralis. Ablative surgery was successful in 52.6% of the procedures, and chronic stimulation in 66%. Stimulation in the ventroposterior group of the thalamus was most effective for peripheral deafferentation pain while ablative stereotaxis on the CM may be more appropriate for patients with central pain or cancer pain. ¿¿