Prostaglandin E2 (PGE2) is commonly considered a potent proinflammatory mediator and is involved in several inflammatory diseases. In the lung, as opposed to many other parts of the body, PGE2 has a role in limiting the immune-inflammatory response as well as tissue repair processes. Understanding the full implications of the regulatory role of PGE2 and how beneficial processes, such as inflammation and tissue repair, become dysregulated to the point of causing disease, might disclose new perspectives in the treatment of pulmonary diseases.