There are three main theories of organizations discussed in the document:
1. Classical theory focuses on the form and structure of organizations, seeing them as systems of differentiated activities with clear divisions of labor, chains of command, and specialized roles.
2. Neoclassical theory recognizes psychological and behavioral issues that question the rigidity of classical theory, noting how divisions of labor can depersonalize work.
3. Systems theory views organizations as existing in interdependent relationships with their environments, made up of interconnected individuals, groups, roles, culture, and physical settings working together as a system.