Many parents are anxious because of the insufficient arch of the feet of their children. A true congenital deformity (congenital vertical talus) is extremely rare. In children the arch is physiologically flattened with a hypervalgus of the hindfoot. Those feet do not need treatment. If there is no medial recess in the footprint in a child over 3 years of age, then we are talking about a flexible flatfoot. When the load of the foot is more pronounced at the medial rather than at the lateral side, operative treatment can be indicated, such as a lengthening osteotomy of the calcaneum. If the flatfoot is rigid, the reason for it is usually a tarsal coalition. Operative transection of the osseous bridge with fat interposition can solve the problem. Flatfeet may also occur in neuromuscular diseases. Depending on the severity of the deformity, splints can be effective, or--in the more severe cases--operative treatment such as a triple arthodesis can be indicated.