A survey about ligamentous injuries of the foot is given by instructive cases. Besides a thorough anamnesis and careful physical examination X-ray-pictures under strain for diagnosis and documentation are recommended. Unlike bone fractures, ligamentous injuries of the foot have received only minor interest to date. This may be partly due to the fact that the rupture of a ligament is only indirectly shown in a standard X-ray film. Such injuries are however more frequent than one would anticipate and it is therefore advisable to search diligently for them following exclusion of a fracture. Thorough physical examination is essential here. In the past arthrography has been the most widely used standard diagnostic procedure; in our hospital however we prefer to use stress roentgenogramms for fresh injuries. Arthrography has two important disadvantages. The leakage of contrast medium into the surrounding tissue demonstrate only capsular rupture, the differentiation between partial and complete rupture of a ligament being not always possible. The spontaneous closure of a rupture by a clot is possible. The major disadvantage of the stress roentgenogramm lies in the fact that it is only advisable within the first 48 h after injury. After this time forced passive movement of a joint must be avoided so that the fine adhesions between the ends of the ruptured ligament are not disturbed. The two procedures can therefore be used complementarily and are not simply diagnostic alternatives.