Robert K. Yin, PhD, before his death in 2026, authored numerous books and over 100 peer-reviewed articles and was founder and CEO of COSMOS Corporation, an applied research and social science firm that successfully completed hundreds of projects for government agencies, private foundations, and other entrepreneurial and nonprofit organizations. Dr. Yin's research covered a wide array of fields, such as primary, secondary, and postsecondary education; health promotion, HIV/AIDS prevention, and substance abuse prevention; organizational development and program evaluation; neighborhood, community, and urban development; and technological innovation and communications.