The differential diagnosis of nonpituitary sellar masses is broad; differentiating among potential etiologies may not always be straightforward because many of these lesions, tumorous and nontumorous, may mimic the clinical, endocrinologic, and radiologic presentations of pituitary adenomas. This article provides an overview of the clinical and radiographic characteristics of both pituitary tumors and the nonpituitary lesions found in the sellar/parasellar region and discusses, in detail, the specific nonpituitary origins of the sellar masses.