“pre-CDM” models can still be adapted to the CDM environment, often with little modification. For example, one of the most critical problems in the planning of GDPs continues to be the deter mination of airport acceptance rates (AAR) for several hours into the future and in the presence of uncertainty about airport capacity and air traffic demand. The efficient stochastic integer program developed for this purpose by Ball et al. (2003) can be viewed as a direct descendant of the pre-CDM model proposed by Richetta and Odoni (1993)