[en] Gas avalanche detectors are instruments of choice for radiation detection and localization in numerous fields of basic and applied research. Recent advances in detection techniques, involving multiplication and detection of single or a few charges deposited in gas media, or emitted from solid converters into gas, are described. The properties of radiation converters and associated advanced gas multipliers are discussed, with an accent on the recently introduced gas avalanche imaging photomultipliers. Applications in the fields of radiation damage studies to DNA, digital mammography and early detection of cancer tumors are presented