With the exception of club foot, flat foot and claw foot, this paper gives a review of principal foot malformations at birth, proceeding from the available radiographical and clinical findings, and also from the facts found during surgery. In addition, there is suggested a classification of various deformities, and there are defined major guidelines and instructions for treatment. As far as the rather frequent polydactylies are concerned, the author distinguishes between a distal phalanx type, an interphalanx type, a proximal phalanx type, a metatarsal type and a tarsal type, depending on the "level", each, where distal/proximal web separation between the fingers stops. It is possible to include also rather particular forms, such as the rudimentary type and the so-called multiplications in this classification. The major indications for the surgical treatment of polydactylies are problems in finding adequate shoes, and also the aesthetic appearance. The principal concern of surgical treatment is to remove additional toes. When there is in parallel a syndactyly or a congenital hallux varus, this may require great skill in the applied surgical technique. Various approaches of surgical treatment are demonstrated by a few examples. Feet oligodactylies are primarily encountered with fibula dysplasia or aplasia, or in cleft feet. In very severe cases it is possible to find just one toe. The actual deformities alone rarely require surgical treatment, but they often "hint at" further malformations in the reach of the root of the foot (synostosis) and of the lower limb. Cleft feet are also frequently impaired in form and function, with these deformities including less severe hypoplasia of a middle toe, e. g. with a somewhat deeper web separation, toe aplasia, metatarsus hypoplasia and aplasia, synostosis, and transversal bones, and even monodactylies with only ray V existing. Additional toes in the cleft foot is one of the rare exceptions. However, the combination of cleft feet and cleft hands is rather frequently encountered. Many cleft feet are nevertheless highly efficient, even without any surgical treatment. That is why there are only indications for a surgical treatment when there are severe foot deformities or most inconvenient misalignments of peripheral toes. Some of the "lobster like" feet are so wide that it is just not possible to wear normal shoes. In this case it is recommended to have surgical correction and to close the cleft. Feet of congenital giant growth are extremely rare, but they raise most complex problems as to adequate treatment. In many cases, an amputation of the additional parts cannot be avoided.(ABSTRACT TRUNCATED AT 400 WORDS)