The RMi system  is based on def,rned inherent rock mass parameters. Basically,  it combines the compressive  strength of intact rock and a jointing  parameter (JP) in the expression RMi :JP represents the main jointing  features, namely block volume (or density of joints), plus roughness, alteration,  and size of the joints. This paper shows how RMi can be applied to a) determine the constants s and m in the Hoek-Brown failure  criterion  for rock masses to assess  the shear  strength parameters  of continuous rock masses; b) work out ground response  curves  using the same s and m constants; c) quantify the descriptive NATM  classification;  d) estimate  stability  and rock support in underground  openings. Rock  support charts  are presented for the three main groups of rock masses: discontinuous  (ointed) rock masses,  continous (massive  and highly  jointed) rock masses,  and weakness  zones. The applications of RMi in rock engineering  probably include a wider range of rock masses  than any other numerical characterization or classification  system.