Remarks on the importance and status of e-p physics simulation for intermediate Q² at HERA

The reasons are emphasized for the importance for physics analysis of event simulation based on adequately realistic models of e-p physics throughput all the available final-state phase at HERA. A survey is made of available recipes and tools for different kinematic ranges of applicability. The problems of building an overall simulation which is both comprehensive and provides a smooth description as a function of final-state variables throughout the accessible phase space are discussed. Where possible, solutions are outlined. The approach is practical in view of the unreality of a simulation which satisfies entirely the demands of theoretical rigour.