There are various reasons why a change of mind concerning traffic policies is demanded. Ecological damage, accidents and property rights are only some examples. The main objective constitutes a shift of traffic from private to public transportation. This paper deals with the question which strategy would be most efficient making bus transportation more attractive to tripper normally using a car. Ajzen's "Theory of Planned Behavior" serves as our basic model of the tourists' motives using a special means of transportation and also helps developing the method used for our inquiry. The results taken from interviews of typical northern Germany tourists show clearly that despite a marked interest in environmental awareness, most trippers see the greater net effects in using a car in order to keep their independency and comfort essential for a likable trip. Therefore, a more quality and efficiency based strategy for marketing public transportation should be recommended. The personal advantage of tourists has to be instrumentalized in favour of environmental conservation.