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The hamstring muscle complex occupies the posterior compartment of the thigh and comprises 3 individual muscles: the biceps femoris (including the long and short heads), semitendinosus, and semimembranosus (see Image. Hamstring Muscles). This muscle group plays a critical role in activities, ranging from upright posture to high-velocity movements such as sprinting and jumping. The region demonstrates a characteristic fusiform-to-elongated contour with a prominent proximal muscular bulk and tapering distal tendinous components. The structural organization of the hamstrings reflects the long muscle bellies arising from the ischial tuberosity, the parallel fiber orientation optimized for force generation and hip extension, and the convergence into cord-like tendons crossing the knee joint. Hamstring injuries are common in both elite and amateur athletic populations, with management strategies ranging from conservative therapy to operative fixation. Intact hamstring tendons exhibit substantial tensile strength and are frequently harvested as autografts in knee ligament reconstruction procedures. Knowledge of hamstring anatomy and function enables accurate injury localization, appropriate grading of musculotendinous pathology, and informed selection of management strategies. An understanding of origin, insertion, innervation, and biomechanical role facilitates distinction between muscle strain, tendon avulsion, and apophyseal injury on clinical examination and imaging. Functional insight into hip extension and knee flexion during high-speed activities supports risk assessment, surgical planning, graft selection, and rehabilitation design, thereby reducing complications and recurrence rates while optimizing return-to-activity outcomes.