All require close collaboration between multidisciplinary specialists (e.g. nuclear physicians and surgeons, sometimes also pathologists). Common goals of such procedures include either less invasive surgeries and/or better control of loco-regional disease. In order to achieve these goals, the target tissue to be surgically excised must be “tagged” using adequate radiopharmaceuticals and adequate administration protocols, as a preliminary phase prior to surgery; in the surgical phase, a hand-held counting probe is utilized to explore the surgical field, thus guiding the surgeon to the tagged lesion. There are currently two main clinical applications, namely radioguided sentinel lymph node biopsy and radioguided localization of occult tumours. Sentinel node procedures have long been used for melanoma and breast cancer, as examples.