This is the Center for Effective Organizations's (CEO) fourth national study of the human resources (HR) function in large corporations. It is the only long-term national study of this important function. Like the previous studies, it focuses on measuring whether the HR function is changing and on gauging its effectiveness. The study focuses particularly on whether the HR function is changing to become an effective strategic partner. It also analyzes how organizations can more effectively manage their human capital. The present study compares data from earlier studies to data collected in 2004. The results show some important changes and indicate what HR needs to do to be effective. Practices are identified that enable HR functions to be high value-added strategic partners.