The Workshop on Hybrid Formulations of Wave Propagat on and Scattering underwent a sequence of iterations before emerging in the format recorded here. These iterations were caused by various administrative and logistical problems which need not be detailed. However, its direction being set initially, the iterations led to modifications of the original concept so that the final form was arrived at through an indirect approach. This circumstance may ex plain some possible deficiencies which might have been removed, had the final concept been implemented directly. The motivation arose from a...