BACKGROUND The congenital hallux varus is a rare hereditary deformity of the big toe, which often is combined either with polydactylia or with systemic deformities of the skeleton. The congenital hallux varus can be easily diagnosed clinically. The X-ray shows the ossified bony elements and provides information about the shape and number of the digits as well as their axial deviation. An operative treatment is required. So far a standardized surgical technique has not been accepted for all types of hallux varus. METHODS The correction of the bony structures and soft tissues is planned by means of preoperative scetches. The amount of correction depends on the degree of the deformity. As consequence of the reorientation of the first ray a soft tissue flap has to be planned and prepared for wound closure which otherwise would need larger grafts. RESULTS Based on this series the clinical and radiological appearance of the congenital hallux varus are discussed. The operative treatment is explained step by step illustrated by photographs as well as planing scetches. Our procedures are compared to other operative methods reported in the literature. CONCLUSIONS There are no diagnostic problems with the hallux varus deformity. For therapy surgery is mandatory and recommended between 9 and 24 months of age. For microsurgical preparation and correction of the deformity planning of all surgical steps and alternatives is advocated, this allows for good functional and cosmetic results.