The development of a triple-GEM imaging detector is reported. The triple-GEM detector provides two-dimensional (2-D) localization of ionizing events making use of a multilayer printed circuit board (X&Y anode) for position readout. Two-dimensional localization is achieved by associating one discrete delay line to each spatial coordinate. Results referring to differential nonlinearity (DNL), integral nonlinearity (INL) and spatial resolution are presented. The detector has been operated with Ar/Xe/CO 2 (64/16/20) gas mixture at atmospheric pressure. 5.9 keV ( 55 Fe source) photons were used to characterize the detector. The feasibility of the imaging technique is demonstrated and the major issues are adressed.Index Terms-Delay line readout, gas electron multiplier, gaseous imaging detector, two-dimensional (2-D) readout.