We study the reliability analysis of a repairable system with m operating units, w warm standby units and R repairmen in which the balking and reneging of units are considered. It is assumed that failed units balk (refuse to join) with a constant probability (1 - b) and renege (leave the queue after joining) according to a negative exponential distribution with parameter r. The failure times of the operating unit and of a standby unit are assumed to be exponentially distributed with parameters lambda and alpha, respectively. The repair time distribution is also exponential. The repairable system is K out of m + w, in which K = 1, 2,..., m. The reliability characteristics, such as the system reliability and the mean time to system failure (MTTF), in a repairable system are derived. Several cases are analysed graphically to study the effect of various parameters on the reliability and MTTF of the system. Copyright (C) 2002 John Wiley Sons, Ltd.