He made his name with his detailed case study investigations of business behaviour and analysis of manufacturing firms, which he characterized as intensely competitive and oligopolistic.
He rejected the concept of individual firm equilibrium in favour of what he describes as the 'steady state' in the industry.
That at the heart of Andrew's story is his argument that manufacturing industry tend to be both oligopolistic and rather competitive in the long run.
This is the methodology that, from Andrews's point of view, misleadingly focuses attention upon the equilibrium position of the firm.
In the long run, Andrews argued, it is 'possible to question the analytical independence of cost and demand functions, which marginal equilibrium theorists take for granted and which, indeed, is essential for the formal validity of their work'.