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The anal triangle is the posterior portion of the perineum by definition. The perineum is located between the thighs and inferior to the pelvic diaphragm. The perineum consists of the anal triangle and the urogenital triangle. A theoretical line connecting the ischial tuberosities of the pelvis divides the perineum into the posterior anal triangle and the anterior urogenital triangle. The anal triangle is bounded by the coccyx, the sacrotuberous ligaments, and an imaginary line connecting the ischial tuberosities. The anal triangle contains the anal canal and 2 ischioanal (ischiorectal) fossae, positioned on either side of the anal canal. The region's boundaries include the posterior margin of the perineal membrane anteriorly, the coccyx posteriorly, the sacrotuberous ligaments posterolaterally, and the levator ani muscle superiorly. The anal triangle has clinical significance in the evaluation and management of hemorrhoids, anal cancer, and perirectal abscesses, which commonly present with pain, bleeding, pruritus, mass effect, or systemic symptoms. From a procedural standpoint, hemorrhoidectomy, Doppler-guided hemorrhoidal artery ligation, stapled hemorrhoidopexy, incision and drainage of abscesses, and oncologic management of anal canal tumors require precise knowledge of regional anatomy, including vascular supply and innervation. Knowledge of anal triangle anatomy and function enables clinicians to interpret symptoms relative to the pectinate line, anticipate differences in pain perception and lymphatic spread, and guide diagnostic evaluation while minimizing iatrogenic complications.