In this paper, the American Institute of Architects (AIA) provides guidelines to help architects understand and use LCA methodology as part of the design process by identifying scenarios for the use of whole building LCA. AIA establishes a basic understanding of LCA for the building industry, the utility of LCA, and proposed suggestions for conducting LCA. The state of research was reviewed to find answers to present limitations of use of LCA in practice. The paper shows that LCA results help answer numerous questions that arise during the design and construction of a green building. It can reinforce the decisions made by architects by providing a scientific justification for those decisions.