In applying catalysis to real combustor applications the modeling of transport and chemistry interactions can be key to understanding combustion characteristics. For example the effect of boundary-layer flow and heterogeneous/homogeneous chemistry can determine product selectivity for catalytically promoted oxidation of chlorinated hydrocarbons. In this paper we discuss parameter regions where different flow models including lumped-parameter-transport laminar boundary-layer and full two-dimensional models can be used for obtaining design insights. The degree of detail required in the gas phase chemistry models and surface chemistry models depends both on the system and the properties to be predicted. Definition of different regimes of operation and limits of applicability for parametric scaling relationships are key to the design of catalytic combustors for incineration or power generation. In addition, a theoretically-based rational strategy for applying catalytic boundary conditions in turbulent flow models would provide a valuable design tool. Examples of alternative modeling strategies are given below along with possible applications for the design of practical catalytic combustion systems.