Our ability to locate resonances of spiral patterns in galaxies is severely limited if spirals are short-lived and if many patterns co-exist in the same galaxy. Theoreticians are currently divided on the basic question of whether spiral patterns are long-lived, but I argue that multiple, short-lived pattersn are to be expected. Bars, on the other hadn, seem to be truly long-lived features and a plausible case can be made that rings in barred galaxies are located at resonances. Even in barred galaxies, however, spirals appear to have a pattern speed that differs from that of the bar.