We present 40 patients operated consecutively for pyloric stenosis during an 8-year period (1981-88). The most common symptom was projectile vomiting, which occurred in 92.5% of the cases. On examination only three patients had a palpable hypertrophic pylorus. In 39 patients, a preoperative x-ray examination with contrast was necessary to confirm the diagnosis. A pyleromyotomy was performed in all patients. We discuss the diagnostic routines and the results of our treatment.