Dr. Farajalla is the inaugural Chief Sustainability Officer at the Lebanese American University. He had worked in the private sector first as a senior scientist at Stone Environmental, Inc., Montpelier, Vermont, USA and then at Dar al-Handasah (Shair and partners), Beirut, Lebanon as a Senior Environmental Engineer on projects which focused on water resources and associated infrastructure, environmental impact studies and management plans, hydrological studies and erosion assessment and mitigation. Dr. Farajalla founded and headed the Land, Water and Environment Department at the consulting firm SETS International with projects in Lebanon, Saudi Arabia, Yemen, Iraq, Egypt, and Oman. He founded and directed the Climate Change and the Environment Program at the American University of Beirut’s Issam Fares Institute for Public Policy and International Affairs. 

His research focuses on the opportunities, challenges, and barriers in the implementation of Agenda 2030 in Lebanon and the region with a special emphasis on integrating the sustainable development goals within an academic framework especially in university campuses and curricula. He also continues to work on the impact of climate change on human settlements and activities through extreme events of flooding and droughts; impact of climate change on security; the nexus of water-energy-food and climate change with focus on adaptation and resilience.

He is currently on the managing board of Blue Peace Middle East which works on using water resources as a means of peace and cooperation in the region. Further, he has collaborated with several UN agencies such as UNESCWA, UNDP, UNDP-RBAS, UNEP-ROWA, and FAO as well as the League of Arab States and other regional institutions.