[¹⁸F]Fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) scans provide patients and referring physicians with diagnostic PET and CT information in a single imaging session. Because most lymphomas show high glucose metabolic activity and FDG avidity, they can be reliably assessed with FDG-PET/CT. PET/CT has emerged as the modality of choice for treatment strategy assessments in patients with lymphoma. Its ability to characterize masses as benign or malignant and its high sensitivity and specificity for staging, restaging, and treatment monitoring have led to widespread acceptance of PET imaging for managing patients with lymphoma.