Student evaluations of teaching effectiveness have been a generally accepted practice among universities in Taiwan. The current practice of using a set of evaluation items for all courses may generate comparable outcomes for administrative purposes, but often falls short in honoring the diverse nature of teaching. This paper presents a web-based customizable evaluation system in National Tsing Hua University, which features a combination of core items, optional items, self-designed items, global items, technical suggestions, and free comments. Comparisons of the evaluation data generated from the paper-based questionnaires and the web-based evaluation system conclude that the web-based system, with more powerful customization functions, is a suitable replacement for the paper-based questionnaires, but the key to the success of the system lies in the interpretation and the utilization of the results.