INTRODUCTION: During the 15t International Congress on Science and Skiing, l gave the lecture "Turning the Skis without Mechanisms of Turning;" however, when performing parallel turns, there is evidently a rotary motion of the skis. This implies the question: "Who turns the skis?" In the first instance, the answer (cf. the title) is not plausible and has to be explained. METHOD: The answer to the question "Who turns the skis?" will be deduced logically and biomechanically. There are two mechanical interactions involved: (1) between the skis and the skier and (2) between the skis and the slope. We have to consider and to compare both. The question is, "How do skiers effect parallel turns?" In order to answer this question, we must first analyze the specific motion of the skis. The ski motion allows us to determine which effects the skis must obtain. Then it is possible to logically deduce which activities the skier can perform to produce these effects and by that the ski motion. 2. Looking more closely at the reality of the skiing process, we find a new problem, From one traverse to the other, the whole system skier/skis changes direction-not only the skis. So we have to ask, "How is the turning of the whole system affected?" The answer will be given by considering the law of the conservation of the angular momentum. By the way of exclusion RESULTS: We have to distinguish two results for the two questions arising from two different views of the skiing process. First, the question of how skiers effect parallel turns (interaction between the skis and the skier) has a simple answer. The skier obviously needs only a few well-known technical elements to produce parallel turns: By means of falling-inward, ski-change and angulation-change, we produce the specific motion of the skis (i.e., inward-drifting and outward-drifting). By leaning-forward and leaning-backward we control the intensity of the turning of the skis. Second, the question of how the turning of the whole system skier/skis is effected (interaction between the skis and the slope) has a very surprising solution: the slope turns the skis! DISCUSSION: We have an absolutely new view of skiing. All ideas existing up to now concerning the ski technique are turned topsy-turvy, We do not turn the skis ourselves: the skis turn us. There is, however, the problem that we have two different Solutions. It seems to be a contradiction that, on one hand, the skier affects the ski motion him/herseif, and on other hand, the slope turns the skis. However, these two solutions are compatible. Even though the slope turns the skis, the skier has to establish an appropriate contact between the skis and the slope. We do this by means of the technical elements mentioned above (see Results 1.). CONCLUSION: The ski technique discovered is variable, because all its elements (activities) have different qualities. In combination of all variable activities, there are infinite possibilities to perform different parallel turns. But in every case, we use the same activities. In other words, we make use of the one and only ski technique. A new understanding of the ski technique requires a new methodical procedure, because Methodics has to be deduced from the ski technique.
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