This paper discusses unique design of the Rush University Medical Center Edward A. Brennan Entry Pavilion, specifically focusing on the sustainable strategies considered and investigated during the design as well as the technical aspects. The first part of the article reviews background information about the Rush University Medical Center and its Entry Pavilion, while the second part of the article reviews sustainable design strategies that were considered as an approach for meeting the Living Building Challenge. Building performance analyses that were performed during the different stages of the design process are discussed in detail. The article also reviews obstacles that were encountered with the Living Building Challenge requirements and lessons learned from this process. The last part of the article discusses the design development, technical solutions and construction of a glass terrarium as one of the distinctive aspects of the Edward A. Brennan Entry Pavilion.