Knee injuries are one of the most common injuries among athletes involved in running sports. From a simple sprain to ligament rupture to surgical repair, rehabilitation is critical in restoring normal function, athletic performance, and prevention of future injuries. The knee joint is a hinge joint comprised of the femur and tibia, between which the medial and lateral meniscus provides a cushion for shock absorption. The primary muscles involved in bending and extending the knee are the quadriceps and hamstrings. The hip muscles, such as the gluteals and calf muscles are indirectly involved to help stabilize the knee in multidirectional movements as well as with power and deceleration of the whole leg. The patella, the kneecap, provides a lever on which the quadriceps attach to extend the knee. The joint is connected and stabilized by the medial and lateral collateral ligaments (MCL and LCL) as well as the anterior cruciate and posterior cruciate ligament (ACL and PCL). Any of these named structures of the knee or a combination of them are often injured in running or jumping sports. Surgical intervention may be required, which almost always is followed by post operative rehab following the surgeon’s protocol. In all cases of knee injuries, the first priority is to stabilize the knee and address swelling as well as pain. Using an assistive device to limit weight bearing may be indicated as well as bracing in the initial phases of injury to achieve such priorities. Rest, ice, compression, and elevation (RICE) is applied. Once the knee is stabilized, if there are no evidence of fractures, physical therapy is initiated. After an initial evaluation is completed to record baseline measurements and goals are established, treatment begins to further promote healing. The next priority is to regain normal range of motion of the knee via manual therapy techniques while using modalities such as ultrasound, electrical stimulation, tape, ice, and/or heat to continue managing swelling and pain. The therapist will also begin developing a therapeutic exercise program involving stretching and strengthening, gradually progressing to training in the gym to improve endurance, power, balance, and agility with sport specific training. With the help of a physical therapist, an athlete dealing with any knee injury will recover as quickly as possible in order to return safely to competition.