“Mrs Penrose was a senior economist in the Merrill/ Johns Hopkins research into the growth of firms and her book was much looked forward to. She does indeed make wise observations, out of her research and her wide reading, about various things which happen, or may happen, in a growing business... A theory of the growth of firms surely should involve generalizations about their economic environment, or, in other words, just those questions about the (equilibrium) structures of industries which the author rules out of court at the start.”