During the years 1950-1973, 229 cases of Achilles tendon rupture were diagnosed in the city of Malmö. More than half of the injuries were caused by sporting activities, the most common being badminton and football (soccer). Ruptures caused by injuries other than sports injuries were found in considerably older subjects. During the period investigated the incidence of Achilles tendon rupture increased in the city more than could be accounted for by changes in the population. This increase could only be partly explained by the increasing interest in sporting activities in the population at risk.