TSU92- is a travel survey that started in 1992 with the aim to increase the knowledge of travels made by unprotected road-users. The survey is still focused on these groups, but questions of other transport modes are also included. An evaluation of the quality of the survey is presented in this report and measures to improve the quality are suggested. The study is limited to sampling errors, nonresponse errors, and measurement errors. The evaluation has been conducted as three separate studies. The aim of the study of sampling errors was to establish variance formulae for estimating the size of the errors and to calculate these variances. The aim of the study of nonresponse error was to examine whether respondents and nonrespondents differ with respect to travel habits and, to examine whether calibration reduces possible nonresponse errors. Calibration is a weighting method that are used to compensate for nonresponse. A follow up study of the nonrespondents was conducted to answer these questions. The aim of the study of measurement errors was to examine the extent of the problem with incorrectly filled-in questionnaires, and to try to understand how respondents think when the answer the questions.