In it, Galbraith asserts that within the industrial sectors of modern capitalist societies, the traditional mechanism of supply and demand is supplanted by the planning of large corporations, using techniques such as advertising and, where necessary, vertical integration.

Galbraith argues that the "industrial system" – by which he means (in general terms) the companies which control around two-thirds of output in key sectors of the economy – are controlled in practice by a technostructure rather than shareholders; he claims that the technostructure does not act to maximise profit (as that involves the risk of failure) but principally to maintain the organisation and, as a secondary aim, to ensure its further expansion.

Risk is diminished, Galbraith says, by advantages large enterprises have in securing longer-term supplier and labor contracts, and by the use of financial instruments such as commodity futures to mitigate volatility in raw materials prices.

Political influence of large industrial concerns in governmental economic and labor policy is cited as another factor that tends to create the stable market conditions that are necessary for corporations' long-term planning of production.

The New Industrial State covers much of the same ground as Galbraith's 1958 work, The Affluent Society, but substantially expands and extends those ideas.