The desire to go beyond the current limits of phase-change memory (PCM) maximum switching speed and energy consumption has lead to increased interest to the investigation of the ultra-fast processes in PCM materials [1]. We present the results of sub-picosecond resolution time-resolved x-ray diffraction studies of the laser-induced structural dynamics in Ge 2 Sb 2 Te 5 as a step towards the non-thermal switching in PCM.