The purpose of this article is to review the clinical utility of FDG and FDG PET/CT imaging in lymphoma and melanoma. A review of the important articles supporting the use of FDG PET imaging in the staging, restaging, and monitoring of response to therapy in lymphoma and melanoma is provided. The intent is to give the nuclear medicine physician and or radiologist the perspective of what may be important clinically to make FDG PET imaging an integral part of the workup of lymphoma and melanoma patients. Specific clinical scenarios and uptake patterns that are unique for lymphoma and melanoma are discussed to ensure relevant and proper interpretation of the FDG PET scans. FDG PET scanning in summary is a useful imaging modality in the staging, restaging, and response evaluation of patients with lymphoma and melanoma.