Welcoming address

It is my pleasure to welcome you on behalf of URSI to the Electromagnetic Wave Theory Symposium. This is, as you know, the third in the series of symposia on this topic initiated by Commission VI of the International Scientific Radio Union. The subjects chosen for the symposium stem from the discussions held at the last General Assembly in Boulder, CO, USA. The central problem in the theory of scattering and diffraction in the form of a boundary value problem remains that of finding a methodology for closing the gap between the low-frequency and highfrequency asymptotic representations of solutions. In fact, there even remains the matter of obtaining the high-frequency representation in a direct manner from the general formulation of the solution, rather than by the semi-heuristic methods now being employed for bodies other than the cylinder and the sphere. We hope that the results presented at this meeting will show some progress toward resolving this very difficult problem.