The equine paranasal sinuses are a frequent site of disease. They are anatomically complex structures encased in bone that are difficult to visualize. Because of their complexity and location, accurate diagnosis and treatment of the affected sinus(es) is difficult without a good understanding of their anatomy. Use of 3-D computer models in anatomy education has increased in recent years and shows promise in teaching anatomy of complex structures. The goal of this thesis was to develop a computer program illustrating a 3-D model of the equine paranasal sinuses to aid teaching the anatomy of the paranasal sinuses. A CT scan of a horse’s head was performed and a 3-D reconstruction was generated. The paranasal sinuses were illustrated in the reconstructed images using Adobe Photoshop 6.0. Adobe Flash Professional CS5 was used to create an interactive computer program from the images. The resulting computer program depicts the sinuses and features of the skull at five key points plus or minus nine degrees of rotation.