The Marris theory considers the Utility associated with managers and owners and the growth of supply and demand.
U Managers = f(Salaries, powers, status, job security)
U Owners = f(profit, capitol, output, public esteem)
Marris argues that the goals of both managers and owners are also very similar as most of the variables in the functions are strongly correlated with a single variable : "The Size of The Firm!"
=> Although they both have different types of utilities (assumed to be selfish), they both want to control the size of the firm and both agree on how it should grow.
U Managers = f(g)d as they want to show shareholders that they have increased interest in the product
U Owners = f(g)s as they want the value of the firm to increase and to own more capitol.
This theory is often compared with Baumol's Sales maximising model and Williamson's Managerial discretion model.
Does that make much sense? I've got an exam in an hour and thought I'd give it a go on my understanding so far.