Pelvic lymph node involvement is an adverse prognostic factor in clinically localized prostate cancer, and a knowledge of nodal status is important for patient management. Whereas nodal disease has been widely regarded as incurable, evidence is now accumulating that some men with lymph node involvement may benefit from radical multimodality treatment approaches. Pelvic nodal status may be assessed by predictive nomograms, by imaging studies and by surgery. The pros and cons of each method are discussed together with the prospects for future development. Optimal strategies combining the different diagnostic approaches for the detection of lymph node metastases are considered in the context of the changing therapeutic implications of nodal disease.