The spleen is a highly specialized intra-abdominal organ that plays an important role in hematologic and lymphatic processes. As with other solid organs, several pathologic entities can originate in the spleen and can carry different short- and long-term risks for the patients. Some of these lesions warrant surgical resection; however, others can be safely monitored. The differential diagnosis of splenic lesions is broad and, in many cases, relies on their cystic or solid nature on imaging. It is important to have a framework for the differential diagnosis of a splenic lesion, as well as indications for surgical referral. This chapter will explore commonly identified splenic lesions, their specific characteristics, and the role of surgery evaluation for each.