Institutional isomorphism

Organisations in the same field tend to grow strangely alike, even when no one is forcing them to and copying brings no obvious advantage. That convergence is institutional isomorphism.

Institutional isomorphism is the tendency of organisations operating in the same field to become increasingly similar in their structures, practices, and forms over time. The concept, from DiMaggio and Powell, explains why organisations often converge not because similarity makes them more efficient, but because of pressures to conform and gain legitimacy.

Legitimacy, not efficiency

The striking claim is that organisations adopt similar forms and practices largely to appear legitimate and appropriate, rather than because those forms work best. Conforming to what is expected, what peers do, what authorities require, what is considered proper, helps an organisation gain acceptance, support, and resources from its environment. So organisations come to resemble one another, copying structures and practices that confer legitimacy whether or not they improve performance. Fitting in, not optimising, drives much of the convergence.

The three mechanisms

DiMaggio and Powell identified three pressures that produce isomorphism. Coercive isomorphism comes from formal and informal pressures, laws, regulations, and demands from those an organisation depends on, that compel conformity. Mimetic isomorphism comes from imitation: under uncertainty, organisations copy others they regard as successful or legitimate, as a safe response to ambiguity. Normative isomorphism comes from professions, as professional training, networks, and standards spread common norms and practices across organisations. Together these push organisations in a field toward a common form.

Why it matters

Institutional isomorphism explains a great deal that pure efficiency cannot. It accounts for why management fashions, structures, and practices spread across organisations regardless of whether they help, why firms in an industry come to look alike, and why reforms are often adopted ceremonially, to signal conformity, while changing little in substance. It is a caution against assuming that whatever organisations widely do must be efficient; much of it may be conformity to gain legitimacy, the safe copying of peers under uncertainty.

Institutional isomorphism is a powerful corrective to efficiency-only views of organisations, showing that the search for legitimacy and the pressures to conform shape organisational forms as much as the pursuit of performance. It explains the puzzling sameness of organisations in a field, the spread of practices that do not obviously work, and the gap between what organisations adopt to look proper and what actually makes them effective.