Because of the role beliefs play in the teaching and learning of mathematics, mathematics educators need to consider ways to assess beliefs and belief change. Beliefs, because they must be inferred, can be difficult to measure, particularly with a common metric that enables a comparison of individuals. Because of the limitations of Likert scales, a computer-based survey was developed to assess beliefs. In this survey, prospective teachers interpret scenarios in a free-response format. The survey, used with more than 150 participants, captures qualitative data that are later quantified for purposes of comparison. A systematic method for creating research rubrics was developed in an effort to quantify the qualitative data. Results from a pre/post administration of the survey demonstrated that it is an effective tool for assessing belief change. In this article the theory behind the development of the survey is discussed, as well as some specific information about the survey and the way responses are coded and a description of the process used for developing rubrics. Recommendations are included for researchers interested in developing similar surveys.