This review considers a number of recent important developments in nuclear medicine, and possible future introductions, priority being given to those products which are most likely to find a place in clinical practice. This includes both novel radiopharmaceuticals and progress with new types of imaging equipment. Three areas are chosen as being of particular importance: brain imaging, heart imaging, and diagnosis and therapy of cancer. In the brain, the clinical value of imaging regional cerebral blood flow and certain aspects of the neuroreceptor/neurotransmitter system are discussed. Cardiac imaging is considered in the light of recent work on diagnosis and risk assessment, investigating the hibernating myocardium, and the possible place of fatty acid imaging. Both diagnosis and therapy of cancer are increasingly important, and the use of radionuclides in these areas is considered.