[en] KENO-IV/CG represents an important step forward in geometric modeling capability for criticality analysis. With the merging of KENO geometry's repeating cell feature and combinatorial geometry's detailed modeling ability and simplified input specifications, many geometric approximations required for previous criticality calculations are no longer necessary. Also, many of the features in KENO-IV/CG lend themselves to further development. Therefore, it represents a step forward in the state-of-the-art for Monte Carlo criticality analysis. All of the problems analyzed with KENO-IV/CG at ORNL have agreed well with experimental data where results are available. KENO-IV/CG provides industry with a very powerful tool for accurately modeling very complex geometries