Public administration as a field of study finds itself in the middle of a fluid environment.  The very reach and complexity of public administration has been easy to take for granted, easy to attack, and difficult to explain, particularly in the soundbite and Twitter-snipe media environment.  Not only has the context for the discipline changed, the institutions of public administration have adapted and innovated to deliver services to the public and serve those in power, while becoming increasingly complex themselves.   Has public administration evolved, and what new lines of research are critical for effective policy and delivery of programs and public services, while preserving foundational principles such as the rule of law and expert institutions?  This Handbook of Public Administration sheds light for new researchers, doctoral students, scholars, and practitioners interested in probing modern public administration's role in solving major challenges facing nations and the world.   This fourth edition recognizes that the scholarship of public administration must reflect the diverse influence of an international orientation, embracing public administration issues and practices in governance systems around the world and illustrating just how practice can vary across jurisdictions.  Every section identifies foundational principles and issues, shows variation in practice across selected jurisdictions, and identifies promising avenues for research.  Each chapter revisits enduring themes and tensions, showing how they persist. along with new challenges and opportunities presented by digital technology and contemporary political realities.  The Handbook of Public Administration, Fourth Edition provides a compelling introduction to and depiction of the contemporary realities of public administration, and it will inspire new avenues of inquiry for the next generation of public-administration researchers.