Modern osteosynthesis has remarkably changed the fracture treatment in small animals with its aim to re-establish full limb function. The scientific basis is elaborated and the different surgical methods are clinically proved. Veterinarians who want to perform operative fracture treatment must have sufficient training in the different techniques, the possibility to perform aseptic surgery and suitable instruments and implants. As this type of surgery means severe stress to the trauma patient, surgery cannot be done before his condition is stabilized.