People re-identification is a fundamental operation for any multi-camera surveillance scenario. Until now, it has been performed by exploiting primarily appearance cues, hypothesizing that the individuals cannot change their clothes. In this paper, we relax this constraint by presenting a set of 3D soft-biometric cues, being insensitive to appearance variations, that are gathered using RGB-D technology. The joint use of these characteristics provides encouraging performances on a benchmark of 79 people, that have been captured in different days and with different clothing. This promotes a novel research direction for the re-identification community, supported also by the fact that a new brand of affordable RGB-D cameras have recently invaded the worldwide market.