The overall aim of this thesis on congenital clubfoot was to estimate the incidence with a national perspective, analyse residual deformities and their management, and evaluate patient reported long-term quality of life and foot function. Paper I was a prospective, nationwide sampling of 280 children with congenital clubfoot during 1995-96. The average incidence was 1.4‰. There was regional heterogeneity but no seasonal variation. Paper II evaluated ultrasonography on 54 newborn, prospectively followed up to 12 months of age. Significant increase of medial malleolus to navicular distance (MM-N-distance) and of soft tissue thickness with increasing age was seen and with acceptable reliability. Paper III assessed 35 children (47 feet) after previous posterior release, mean age of 4.5 years, and the MM-N-distance was shorter in unilateral clubfeet (21 patients) than in contralateral normal feet. No association between navicular position and forefoot adduction (FFA) was determined. Smaller FFA yielded better subjective and functional outcome. Paper IV reviewed distraction treatment with Ilizarov External Fixator in seven patients (10 feet), 6-15 years of age, with relapsed deformities. All patients, except one, reported satisfaction with the overall result but less stiffness was experienced in only 4/10 feet. Paper V evaluated self-estimated outcome in 83 patients (63 males, 20 females), mean age of 64 years, through SF-36 and EQ-5D, and through AAOS foot and ankle score. Age and gender adjusted norm groups were used. Female patients scored worse than male patients did. Both males and females reported negative influence on foot and ankle function. Conclusion: The incidence of congenital clubfoot in Sweden is higher than in previous Scandinavian studies. Ultrasonography is reliable for describing pathoanatomy of the talo-navicular joint in clubfeet and can detect "spurious" (false) correction. Distraction treatment with the Ilizarov External Fixator yields subjective improvement but stiffness remains. Long-term influence on daily life activities is limited to foot and ankle function for both genders, but only female patients report negative influence on physical aspects of quality of life.