Administrative law is the body of law that governs the activities of administrative agencies of government. Government agency action can include rulemaking, adjudication, or the enforcement of a specific regulatory agenda. Administrative law is considered a branch of public law. As a body of law, administrative law deals with the decision-making of administrative units of government (e.g., tribunals, boards or commissions) that are part of a national regulatory scheme in such areas as police law, international trade, manufacturing, the environment, taxation, broadcasting, immigration and transport. Administrative law expanded greatly during the twentieth century, as legislative bodies worldwide created more government agencies to regulate the increasingly complex social, economic and political spheres of human interaction.