This study aims to develop a way to convince stakeholders to adopt sustainable building practices. The network of numerous stakeholders that are involved in building projects can influence the process of adopting sustainable building practices, and the complexity of building projects requires a more integrated way of collaboration to adopt new practices. The existing excess inertia among stakeholders has resulted in the sluggish adoption of sustainable and energy efficient design and technologies in the building sector. This study includes buildings that both have and have not adopted Leadership in Energy and Environmental Design (LEED) and retrospectively identifies organizations that are involved in projects in order to understand the trajectory of the adoption process and the diffusion among stakeholders in projects. The study proposes to identify the role of stakeholders as early adopters and opinion leaders in the adoption process and to examine how these stakeholders’ relationships evolve as LEED, a voluntary, market-driven mechanism, becomes to government standards in 2007 in New York, NY. This study investigates; 1) the effect of stakeholders’ previous exposure to sustainable building projects (SPES) on the adoption of sustainable building practices, 2) the interaction between SPES and the role of stakeholders on the adoption of sustainable building practices, 3) the interaction between SPES and type of project delivery systems on the adoption of sustainable building practices, and 4) the difference in three associations above before and after LEED became government standard. A directory of newly constructed or renovated office buildings completed between 1998 and 2013 in New York, NY for both LEED and non-LEED certified buildings is obtained from Emporis database. Then, I search these building projects in U.S. Green Building Council (USGBC) database to obtain the levels and credits of LEED achieved. I also invite companies involved in the projects to a web-based questionnaire to acquire detailed information of the projects. Independent variables are the stakeholders’ role in the project, their previous exposure to sustainable building practices, the delivery system used in the project, and timing of completion of project whether it is before or after government green building procurement. Other building characteristics (i.e., type of project, height, total square footage) are statistically controlled in the analysis. A dependent variable is the outcome of LEED certification as building sustainability. Depending on the type of the response variables, three different statistical approaches are used: multiple logistic regressions for a dichotomous response (LEED vs. non-LEED), cumulative logistic models for an ordinal response (levels of LEED: platinum, gold, silver, certified), and multiple regression models for a continuous response (the number of credits achieved, 0-110). The expected outcomes indicate the importance of the SPES in the adoption of sustainable practices and the moderating effects of the role of stakeholders and the type of project delivery methods. The outcomes also imply that there is an effect of government requirements on the association between SPES and the project sustainability outcome. Overall, this study contributes to a greater understanding of which stakeholder/organization tends to become an early adopter or an opinion leader, how these early adopters and opinion leaders change within the certainty of demand when voluntary, market-driven certification turns into a mandated requirement.