A guidance system (SG) for an individual (IND) moving in an unknown environment establishes a guidance loop (B) between a measurement module (MM) placed on the individual and a remote guidance platform (PG). In the measurement module, a means (CP) collects measurement data (DM) that are transmitted by another means (UC1) of transmission to the guidance platform via a first communication channel. Then, at the guidance platform, a means (UT2) determines the tactical position data (DST) from the transmitted measurement data (DM), and another means (UC2) transmits determined guidance data (DG) from the tactical position data to a communication device of the individual by means of a second communication channel (R2), thus closing the guidance loop.