Over recent decades, the global focus on climate change and on conservation of resources has brought about a paradigm shift in the adaptive reuse of old and historic buildings. Adaptive reuse is now seen as a key factor in the conservation of land and environment, preservation of cultural identity, and reduction of urban sprawl. Increasingly, engineers, architects, and urban planners are making concerted efforts to realize the reuse potential of existing and outdated structures. Therefore, those involved in building design have studied the viability of adaptive reuse and generally favor the repurposing of old/historic buildings to suit new patterns of occupancy and use without disturbing the environment or increasing carbon footprints. Redesign and reconstruction through refurbishment, remodeling, renewal, repair and retrofitting is carried out to meet new requirements and provide performance that was not in the original design. Buildings are one of the largest energy users in the United States.[1] In total, buildings used around 40 percent of energy in 2015, which accounts for the largest share among forms of energy consumption. Many of the buildings are not energy efficient but do have historic value; while giving them a new purpose, their historic legacy can also be preserved. There are many challenges like program modification feasibility, structural issues and energy efficiency which need to be addressed during pre-construction and can be addressed by careful planning and innovative techniques. To understand the various challenges involving adaptive reuse, this study employs the Clark Hall at the University of Massachusetts to test the efficacy of design and performance interventions. Clark Hall was originally used for science classes and botany research and later was converted into painting studios. Presently the building structure is still intact, provides enough room for program modification, and has significant reuse potential. Therefore, Clark Hall is a suitable candidate for adaptive reuse as an academic office building that satisfies contemporary building standards and meets the growing demand for office space. Through this project, an attempt has been made to explore and understand the complexities and challenges as well as the various possible ways to change the function of Clark Hall from a defunct structure to a modern energy efficient and environmentally sustainable academic office building with measures for energy conservation through contemporary innovative design approaches. The research work begins with a background study of the building’s history and its different purposes, along with three precedent studies of contemporary and innovative design examples. It also identifies relevant local, federal, and state building and zoning regulations and incorporates existing energy-saving technologies and materials appropriate to Clark Hall. Keeping in mind the financial viability of project, an attempt has been made to control and bring down the operating and the maintenance costs by carrying out extensive energy modelling and simulations to support these recommendations. In conclusion, the final outcome of my project is a design plan for the adaptive reuse of Clark Hall as a new energy efficient and environmentally sustainable office building for the benefit and the use of University of Massachusetts Amherst that mitigates costs and improves design utility and aesthetics, while preserving its historic value. [1] According to the U.S. Energy Information Administration, “in 2017, about 39% of total U.S. energy consumption was consumed by the residential and commercial sectors.” https://www.eia.gov/tools/faqs/faq.php?id=86&t=1. October 2018.