© Academy of Management Journal 1980, Vol. 23, No. 4, 591-614. Momentum and Revolution in Organizational Adaptation^ DANNY MILLER McGill University, and Ecoie des Hautes Etudes Commerciaies, Montreal PETER H. FRIESEN McGiil University The change in 24 structural and strategy making vari- ables over time is analyzed by a study of 26 companies. Organizations were found to resist reversals in the direc- tion of change in strategy and structure. Two extremes were demonstrated: periods of momentum in which tittte or no trend is reversed and dramatic periods of rev- olution in which a very great many trends are reversed. The one theme that stands out in the literature is that organizations tend to demonstrate great sluggishness in adapting to their environments. Orga- nizations often resist change even when their environments threaten them with extinction (Hedberg, 1973, 1974, 1975; Maniha & Perrow, 1965; Hedberg, Nystrom, & Starbuck, 1976). This may be due to the pursuit of stability and avoidance of uncertainty (Carter, 1971), the programming of activities and the reluctance to deviate from programs (March & Simon, 1958), the inability to innovate (McGuire, 1963), the incapacity of firms to appraise accurately their own performance (Wildavsky, 1972), executives' narrow and parochial models of external reality (Hedberg et al., 1976), and the economies of stability (Perrow, 1972). Any findings on the adap- tive process would be expected to refiect the problems caused by natural resistance to change. The literature seems to emphasize this resistance almost exclusively and to point out the advantages, in certain environments, of organizations that are loosely structured, organic, and oriented toward product-market inno- vation, open communications, expert-based power, etc. (Burns & Stalker, 1961; Thompson, 1967; Galbraith, 1973; Lawrence & Lorsch, 1967). More timely and presumably effective responses are expected to take place given such orientations. Yet there seems to be a bias in this point of view. Histories by Filgas (1967), Wilson (1954,1968), Hower (1943,1949), Moore (1945) and others 'The authors are grateful to the Canada Council for Grants #S76-0378 and 410-77-0019 and to the Government of Quebec for FCAC Grant #EQ1162. 591