The IRG has contributed several blocks of characters to Unicode/UCS, including the CJK Unified Ideographs, CJK Compatibility Ideographs, CJK Unified Ideographs Extension A, CJK Unified Ideographs Extension B, and others. CJK Unified Ideographs Extension C is in preparation.
Note that the accusation that Unicode may destroy Asian countries' culture is countered by the fact that decisions on Han Unification are made primarily by Asian experts. Similarly, the fact that the Unicode Consortium and ISO/IEC 10646-1 decided to unify Han characters before the creation of the IRG, is countered by the fact that this decision was made by Asian members of both organizations.