This paper considers the issues surrounding the representation of planning policies in land-use and land-use/transport interaction modeling. The examples presented in the paper are related to the authors work in the United Kingdom (UK) with the DELTA package, but the issues are general and relevant to other models and to other planning systems. The paper considers: (1) the need to represent planning policies in land-use and land-use/transport interaction modeling; (2) general issues that arise in trying to represent planning policies, especially for the long-term; and (3) more specific issues in representing and assessing planning policies within formal models.