Pheochromocytoma or secreting paraganglioma may recur after initial surgery. Diagnostic methods have improved in recent decades. We determined whether features at presentation have changed over time and are associated with long-term outcome. In 192 patients with pheochromocytoma/paraganglioma seen between 1975 and 2003, we compared time from onset of hypertension to first operation, total metanephrine excretion, tumor size and site, the proportion of cases presenting as incidentalomas, and the probability of recurrence according to date of operation (divided into quartiles). The duration of hypertension and tumor size at first operation decreased significantly over time. Right-sided adrenal tumors were more frequent and larger, excreted greater amounts of metanephrines, and presented more frequently as incidentalomas than left-sided tumors. Age, familial disease, and tumor site and size were independent predictors of recurrence. The risk of recurrence was 3.4-fold higher in patients with familial disease than in those with sporadic tumors; it was, respectively, 3.1- and 11.2-fold higher in patients with right adrenal and extraadrenal tumors than in patients with left adrenal tumors. In conclusion, pheochromocytomas/paragangliomas can now be diagnosed earlier, with smaller tumors, and more frequently as incidentalomas. Familial, right adrenal, and extraadrenal tumors recur more frequently than left adrenal tumors.