Software tools can only be effective if users accept them. Investigating user acceptance requires a model explaining people's attitudes and behaviour as well as reliable and valid measurement instruments. This paper applies Davis' technology acceptance model (TAM) and its question naire-based measurement instrument for evaluating a newly developed Web-based inspection data collection tool (WIPS) from a user's perspective. TAM postulates that two particular user beliefs, usefulness and ease of use, predict tool usage and, thus, tool acceptance quite well. To investi- gate this and to assess the usefulness and ease of use of WIPS, we performed an experiment with computer science students as subjects.Our experimental results confirmed the reliability and the validity of the TAM and its questionnaire. Moreover, WIPS received high ratings for both TAM determinants. These results, together with the fact that usefulness was corre- lated to self-predicted future usage, explain why most of our subjects preferred WIPS over paper-based forms for inspection data collection.The reliability and validity of the TAM questionnaire is not limited to inspection tools, but applies to the user acceptance evaluation of tools and techniques in general. We demonstrate this with data from an experiment we performed in an industrial setting with professional software developers to evaluate different inspection techniques.