This chapter introduces the key concepts of international human resource management (IHRM). It defines IHRM and differentiates it from domestic HRM, noting IHRM involves more complex activities and broader external influences. The chapter outlines five variables that moderate the differences between domestic and international HRM: cultural environment, industry type, reliance on the home country labor market, and senior management attitudes. It provides frameworks for analyzing IHRM strategically and how the context continues to change.