This paper reviews possible uses of remote-sensing techniques to locate avalanche victims. Until recently probes and dogs were the only methods available, but recently attempts have been made to devise other methods for finding human beings in snow. Ideally such a search should be made possible for other members of the party, as the chance of survival of a victim falls rapidly with increasing time to rescue. For this all members of the party need to have something which the others can locate. The most usual proposal is an electromagnetic transmitter/receiver set. The merits of various possible frequencies are discussed. International agreement on a frequency is urgently required. Magnetic devices might be considered, but the detecting devices are too expensive or heavy to be generally carried. Search parties can of course be equipped with more sophisticated apparatus, and various possibilities are discussed for identifying metal on the victim, for identifying him by radio sounding, for locating him by mapping microwave emission, or for searching for eddy currents induced in him.