A large and growing body of research exists on how the design of the environment can positively or negatively affect people’s health and well-being, as well as influence their behavior. Researchers in this field, known as “environmental design research,” have long acknowledged the challenge of translating their findings into formats that are accepted and used by practitioners. This study explores how environmental design research on urban open space and the practice-oriented translations of it are used by landscape architects who have been recognized in the profession for their designs of parks, plazas, and streets in urban areas. Through interviews with practitioners, an understanding emerges of the impact of environmental design research on contemporary practice, leading to recommendations that could enhance it in the future. Key findings of the study indicate that translations of the research, specifically in the form of design guidelines, while intended to inform practice, are not widely used by designers. Rather, to understand how design impacts human behavior, practitioners rely primarily on what they refer to as intuition, largely informed by their own direct observations of people in public space. The quality of their personal observations, therefore, is critical to their depth of understanding of human behavior and the environment. The study concludes with recommendations that could improve the skills of design students and practitioners to conduct, interpret, and apply their own direct observations in their designs, using methods and findings from the field of environmental design research to inform and enrich this process.