© Springer-Verlag Berlin Heidelberg 2016. Metastasis refers to the spread of malignant cells to a site or sites distant from a primary cancer’s location. In the setting of uveitis, metastatic lesions may produce a true uveitis that is an inflammatory response to malignancy within the eye. Metastatic disease may also result in an appearance mimicking a uveitis, wherein the cellular reaction is composed of malignant rather than inflammatory cells. Lung and breast cancer are by far the most common, respectively representing 37 and 23 % of all cases, but numerous other primary sources of malignancy have also been reported, including esophageal, pancreatic, germ cell, ovarian, Ewing’s sarcoma, and melanoma. Finally, treatments for metastatic disease may produce a drug-induced uveitis.