Historically, pelvic fractures have been classified according to whether there is pelvic stability or instability, although confusion has been caused by the inclusion of many eponyms that mainly reflect the observation of a single author on a particular fracture pattern. Pennal and Tile were the first authors to attempt to classify pelvic fractures according to the force vector causing them. This concept was refined by Young and Burgess, who provided a more detailed classification system, again relating to force vectors. This article focuses on this classification and its significance with regard to pelvic stability, type of pelvic disruption, and hence the type of corrective forces that should be applied in the surgical management. Use of a classification system of pelvic fractures based on force vectors allows the orthopedic surgeon to apply external fixation in the most appropriate manner to correct pelvic deformity and to maximize patients' survival.