Exact and closed-form expressions for the level crossing rate and average fade duration are presented for the M-branch Pure Selection Combining and for the two-branch Threshold Selection Combining schemes. assuming independent branches in a Rayleigh environment. The analytical results are thoroughly validated by reducing the general case to some special cases. for which the solutions are known. and by means of simulation for the more general case. The plots presented here are also compared with those of the general solution recently published for the Equal Gain and Maximal Ratio Combining and an agreeable coherence is found. Copyright (C) 2001 John Wiley & Sons, Ltd.1410897907