Order Review/Release (ORR) activities have mostly been ignored in past job shop research. In most previous studies, arriving jobs are immediately released to the shop floor without considering any information about the system or job characteristics. In practice however, these jobs are often first collected in a pool and then released to the system according to a specific criterion. Although practitioners often observe the benefits of ORR, researchers have found limited support for the use of these input reglation policies. One objective of this paper is to examine this research paradox in a capacitated system. We also offer a new classification framework for existing research work. Finally, for the first time in this paper, both periodic and continuous ORR methods are compared simultaneously under various experimental conditions against different performance measures. The results of simulation experiments and statistical tests are also presented in the paper. (C) 1999 Elsevier Science B.V. All rights reserved.