Under the guidance of the UIC, research groups did a number of investigations on ride comfort and later also on ride comfort in tilting trains. The latest study started in the early 2000. At the same moment the UIC group started on urgent demand of the members, the preparation for a campaign that would investigate the onset of nausea in tilting vehicles. The problems to overcome were so important that the cooperation with universities and industry was necessary. A consortium was built and negotiations with EU started in order to have the possibility to participate in the fifth frame program competive and sustainable growth. The EU gave the permission to start, but we had the obligation not only to investigate onset of nausea but also the relation between geometry of the track, limits in different countries, cross boarding and tilting trains had to be investigated. Conclusions from the project are: - A method is found and applied that permits a regression analysis of the results test runs who investigate nausea; - Key elements in the new method are: net dose evaluation of the parameters having influence on nausea, excel solver like optimising of parameters like time constant; scale factor and regression constant (Or a binary method finding local extreme); - The time constant found for the net dose evaluation is close to 10 minutes; - Weighting improves the quality of the regression in a significant manner for vertical and lateral acceleration (Exception SNCF ?); - Prof. Dr Griffin's vertical weighting function is suitable for this purpose.; - Age differences in the test group are a serious disturbing factor; - Also reuse of test persons is a serious disturbing factor; - Vertical acceleration is oft but not always the best suited regression parameter in the test group, roll velocity is close to vertical acceleration.; - Proper weighted vertical acceleration is the best common describing parameter among the various test conditions in the Nordic and southern line tests; - The morning southern tests are a clear exception, for this test situation, no good describing factor is found; - Some elements in the Southern tests let suspect for and aft vibration as a explaining factor; - Unweighted for and aft vibration was better then the weighted vibration acceleration, this could signify that the weighting function was not proper: - Two methods permits to describe global nausea evaluation: average nausea evaluation, percentage of people signalling at least Scale 1 on a scale from 0 to 7; - From the second method we have observed that in some occasions up to 50% of the tests persons do feel something; - In many situations male seem to be less sensitive than women.