This paper overviews various methods of data acquisition from GEM detectors. Presented are currently working systems in tokamaks. The data acquisition methods are divided into two parts. First part, devoted to analog signal processing, describes different approaches for signals acquisition, i.e. pulse amplifying and shaping, ASIC use, delay lines. Digital data acquisition part describes presently used high speed interfaces and system standards. Described are also different approaches for data handling, i.e. online analysis, data reduction, system topologies.