External fixation is an essential tool for the management of fractures and other musculoskeletal injuries. Despite a long history of use in the field of orthopedic surgery, modern external fixation continues to expand its applicability with increasing modularity and ease of application. Provisional applications are a fundamental tool for fracture care and allow for temporizing management of injuries which may include soft tissue or vascular compromise, compartment syndrome, or polytrauma. An understanding of biomechanics, anatomy, and indications is important for safe and effective application of external fixators. Careful pin insertion technique is vital to minimizing the risk of pin-site infection and loosening. Though an expanding catalog of modern implants is available, the surgeon is able to care for a wide variety of lower extremity injuries through an understanding of key principles of implant selection and construct design.