New developments in positron emission tomography–computed tomography (PET-CT) have included the introduction of scanners with multidetector 16- to 64-row CT that allow thin-section essentially isotropic imaging datasets to be acquired rapidly in multiple time phases. “Diagnostic quality” CT with both oral and intravenous enhancement is now routinely possible in PET-CT and allows greater potential for the accurate diagnosis and staging of the full range of cancers involving the abdomen and pelvis. This article explores the considerations for more tailored, specific tumor-related protocols for PET-CT in the abdomen and pelvis, with emphasis on the use and value of fully optimized CT as part of an integrated PET-CT examination.