Urban design review has traditionally been fraught with allegations of subjectivity. While reviewers strive to ensure projects that are in the best interests of the community, the mechanisms for and language of evaluation are often arbitrary and inconsistent. With any evaluation process, the more objective and standardized the assessment instruments are, the more assurance is afforded by the community. The proposed ‘urban design assessment model’ is one mechanism based on the mathematical concepts of fuzzy set theory that attempts to address this problem, while assuming a role as a tool to complement rather than supplant existing mechanisms of review. The paper is presented in four parts. The first part is the introduction to the paper. The second part briefly explains the term ‘urban design’ and the different approaches to urban design review. The third part describes the proposed urban design assessment model. This section also discusses the basic concept of the fuzzy set and explains the model through an example. In the fourth part, the conclusion of the paper, the strengths and weaknesses of the proposed model are examined