Where is the limit, in this field, of the computer's role? Is there, on a short-term basis, further progress to be made? 1. The aim of the advertising message; 2. The factors enabling us to attain this aim; 3. The two levels of the media-planning problem; 4. At the first level the problem is scientifically solvable, with accuracy; 5. The solution of the problem on the second level, on the other hand, depends on empirical methods; 6. The interest of the division into two levels is to permit the media planners to use data processing only with full knowledge of the case, and deliberately; 7. On a short-term basis the only real progress remains tied at the first level to the operational aspects of data processing; 8. The TOM-Terminal System: a solution to media-planning in "time-sharing" on the European level.