Some experts suggest that urban design plans in US cities may lack adequate coverage of the three-dimensional design aspects of the built environment. 3D digital models may help designers visualize and interact with design alternatives, large urban data sets, and 3D information more effectively, thus correcting this problem. Case studies of recent urban design plans that have used 3D digital models may indicate whether these technologies can increase the quality of the plan. This research discusses the role 3D urban models can play in supporting designers in addressing the 3D design aspects. A literature review focused on reviewing secondary sources to construct or adopt theoretical propositions against which the empirical data can be compared and contrasted. A case study involved investigating the methods with which 3D models have been used in developing a selected urban design plan. The content analysis of the case study refuted the premise that the plan would inadequately address 3D aspects and utilize 3D information, and indicated an effective usage of 3D modelling to analyze and represent most of the 3D and 2D information elements and issues. The results are consistent with a hypothesis that the effective usage of 3D modelling would result in the effective coverage of 3D information and issues. The effective usage of the modelis functionalities has improved the quality of the decision-making process through improving designersi cognitive capabilities and providing a platform for communicating design ideas among and across design teams