In it, he popularized a useful model of the evolution of management theory in the United States. His model includes classical, human relations, and human resources management. The Classical school of thought began around 1900 and continued into the 1920s. Traditional or classical management focuses on efficiency and includes bureaucratic, scientific and administrative management. Bureaucratic management relies on a rational set of structuring guidelines, such as rules and procedures, hierarchy, and a clear division of labor.
Administrative management emphasizes the flow of information in the operation of the organization.
Bureaucracies are founded on legal or rational authority which is based on law, procedures, rules, and so on. Positional authority of a superior over a subordinate stems from legal authority. Charismatic authority stems from the personal qualities of an individual. Scientific Management Scientific management focuses on worker and machine relationships. Organizational productivity can be increased by increasing the efficiency of production processes.