The elements of organizational structuring---which show a curious tendency to appear in five's---suggest a typology of five basic configurations: Simple Structure, Machine Bureaucracy, Professional Bureaucracy, Divisionalized Form, and Adhocracy. The elements include (1) five basic parts of the organization---the operating core, strategic apex, middle line, technostructure, and support staff; (2) five basic mechanisms of coordination---mutual adjustment, direct supervision, and the standardization of work processes, outputs, and skills; (3) the design parameters---job specialization, behavior formalization, training and indoctrination, unit grouping, unit size, action planning and performance control systems, liaison devices (such as integrating managers, teams, task forces, and matrix structure), vertical decentralization (delegation to line managers), and horizontal decentralization (power sharing by nonmanagers); and (4) the contingency factors---age and size, technical system, environment, and power. Each of the five configurations relies on one of the five coordinating mechanism and tends to favor one of the five parts. In Simple Structure, the key part is the strategic apex, which coordinates by direct supervision; the structure is minimally elaborated and highly centralized; it is associated with simple, dynamic environments and strong leaders, and tends to be found in smaller, younger organizations or those facing severe crises. The Machine Bureaucracy coordinates primarily by the imposition of work standards from the technostructure; jobs are highly specialized and formalized, units functional and very large (at the operating level), power centralized vertically at the strategic apex with limited horizontal decentralization to the technostructure; this structure tends to be found in simple, stable environments, and is often associated with older, larger organizations, sometimes externally controlled, and mass production technical systems. The Professional Bureaucracy relies on the standardization of skills in its operating core for coordination; jobs are highly specialized but minimally formalized, training is extensive and grouping is on a concurrent functional and market basis, with large sized operating units, and decentralization is extensive in both the vertical and horizontal dimensions; this structure is typically found in complex but stable environments, with technical systems that are simple and non-regulating. In the Divisionalized Form, a good deal of power is delegated to market-based units in the middle line (limited vertical decentralization), whose efforts are coordinated by the standardization of outputs, through the extensive use of performance control systems; such structures are typically found in very large, mature organizations, above all operating in diversified markets. Adhocracy coordinates primarily by mutual adjustment among all of its parts, calling especially for the collaboration of its support staff; jobs are specialized, involving extensive training but little formalization, units are small and combine functional and market bases in matrix structures, liaison devices are used extensively, and the structure is decentralized selectively in both the vertical and horizontal dimensions; these structures are found in complex, dynamic environments, and are often associated with highly sophisticated and automated technical systems. In conclusion, it is claimed that the effective Organization will favor some sort of configuration---some type of a logically consistent clustering of its elements---as it searches for harmony in its internal processes and consonance with its environment. But some organizations will inevitably be driven to hybrid structures as they react to contradictory pressures or while they effect a transition from one configuration to another, and here too it is believed that the typology of five can serve as a diagnostic tool in organizational design.