Prostate cancer is the most common malignancy in men in the Western world and represents a major health problem with substantial morbidity and mortality. Sensitivity and specificity of digital rectal examination (DRE) and evaluation of prostate specific antigen (PSA) are excellent methods for diagnosis of prostate cancer, but have limited value for staging. Imaging of prostate cancer has become increasingly important to improve staging and management of prostate cancer patients. Conventional imaging modalities, such as transrectal ultrasound and computed tomography, show limited accuracy for a reliable assessment of prostate cancer. Diagnostic value of magnetic resonance imaging has improved by dynamic contrast enhancement (DCI-MRI) and diffusion-weighted magnetic resonance imaging (DWI). Recently, substantial progress has been made in the development of functional and molecular imaging modalities, such as positron emission tomography using radiolabeled metabolic tracers, receptor-binding ligands, amino acids, peptides, or antibodies. Here, we review the value of these novel radionuclide imaging techniques in the assessment of prostate cancer. Prostate 72:12621272, 2012. (C) 2011 Wiley Periodicals, Inc.