Abstract: Dr. Ouathek Ouerfelli directs the Organic Synthesis Core Facility (OSCF) at Memorial Sloan Kettering Cancer Center (MSK) since 2004. He is committed to continue to provide chemistry services for the MSK research community and the development of new tools and therapeutic agents for cancer detection, prevention, and treatment. His core services have been extended to Weill Cornell Medical College in 2019 through an inter-institutional agreement. He possesses more than 30 years of chemistry collaborations and service of MSK investigators, about half of whom are NCI grantees. Along these lines, he contributed to major endeavors by eminent colleagues who are NCI grantees such as Dr. Charles Sawyers (R01 CA155169) which led to an FDA-approved drug, Dr. Howard Scher (P50 CA092629) with projects that are showing promise, as well as Dr. Larry Norton (P01 CA094060) for the development of a topical treatment to chemo- induced alopecia among others. Dr Ouerfelli maintains a state-of-the art facility with expert professional personnel in chemical synthesis. OSCF has now the capability to support medicinal chemistry efforts to evolve agents in support of MSK investigators. Under his leadership, the core has greatly facilitated preclinical studies at the Center.