This paper examines the perceived effectiveness of various human resource management practices by United States supervisors in the United States Foreign Service. It attempts to identify, through the review of current human resource management literature and interviews with ten U.S. Foreign Service Diplomats in Residence, best practices for managing and motivating a foreign national workforce to perform under United States guidelines. The identification of best practices will conclude with a case study of my own experience supervising a foreign national staff during a turbulent time. The conclusions that are drawn throughout this paper and their implications for developing a strong and motivated foreign national workforce identify cross-cultural appreciation as imperative to successful human resource management across a wide spectrum of personnel management experiences. This paper is a practical tool for any U.S. citizen contemplating a career as an officer in the Foreign Service and on a broader scale for any international human resource manager, particularly those working in the public sector, to understand the importance of cross-cultural awareness to successful human resource management and organizational sustainability on the whole. And from the perspective of non-U.S. citizens who work for U.S. organizations, this paper may serve to provide insight into the management styles considered effective by U.S. supervisors.