The ATLAS experiment will efficiently reconstruct and identify muons, using data recorded by different sub-detectors. Muon tracks will be reconstructed in the inner tracking system and in the outermost muon spectrometer, exploiting both the solenoidal and the toroidal magnetic fields for momentum measurement; the corresponding energy deposits in the calorimeters will also be measured. Here we present the algorithms developed to combine these reconstructed quantities, in order to obtain a robust and precise muon identification capability. The peculiarities of each possible combined reconstruction technique will be discussed and the corresponding performance, evaluated on simulated samples, will be reported