The focus in this study is on evaluating scheduling policies that may be us
ed to offer a near-perfect delivery performance for vital customers in dual
resource constrained (DRC)job shop environments. Prior studies in this are
a have modeled shops where all orders are considered to be of equal importa
nce, and shown that any reasonable combination of worker assignment and dis
patching rules that are sensitive to the shop cost factors modeled works we
ll. However, a recent survey indicates that shops do in fact distinguish am
ong orders on the basis of customer identity, and that certain customers ha
ve very rigid delivery guidelines which must be adhered to in order to main
tain their ongoing business. The present study models such environments, an
d shows that the choice of scheduling policies is not inconsequential, espe
cially if the shop aims at providing near-perfect delivery performance to a
limited set of customers. In such instances, policies for deploying worker
s to different departments, as well as dispatching rules that use customer
identity based information outperform their counterparts that are not sensi
tive to orders placed by vital customers.