The pectoralis major and pectoralis minor are part of the anterior axio-appendicular musculature and are essential for shoulder and upper arm movement, aiding in activities such as pushing, lifting, and throwing. With the rise in weight training and sports, pectoralis major injuries have become more common. Understanding the complex tendo anatomy of these muscles is critical for accurate imaging interpretation and characterization of tear patterns to allow optimal treatment. The muscle group is also subject to other pathologies including thoracic outlet syndrome, Poland syndrome, neoplasms, as well as accessory muscles which may mimic pathology. This chapter discusses imaging techniques, including ultrasound and MRI, and reviews the injury patterns and other common pathologies.