I don't remember much about it but I recall it was a blistering satire of capitalism, advertising and consumerism, and could only have been written as science fiction (it was written in the 1950s). In those days, it would have been considered Communist propaganda and gotten the author in trouble if published as mainstream fiction, much like Vonnegut's "Player Piano" did. The two books are often compared by critics.

From the Wikipedia Entry

In a vastly overpopulated world, businesses have taken the place of governments and now hold all political power. States exist merely to ensure the survival of huge trans-national corporations. Advertising has become hugely aggressive and by far the best-paid profession. Through advertising, the public is constantly deluded into thinking that the quality of life is improved by all the products placed on the market. Some of the products contain addictive substances designed to make consumers dependent on them. However, the most basic elements of life are incredibly scarce, including water and fuel.

...

In his study of the pioneers of science fiction, New Maps of Hell (1960), the novelist Kingsley Amis states that The Space Merchants "has many claims to being the best science-fiction novel so far." It is also ahead of its time in stressing the importance of limiting population growth and conserving natural resources. On its initial publication, Groff Conklin called the novel "perhaps the best science fiction satire since Brave New World." Boucher and McComas praised it as "bitter, satiric, exciting [and] easily one of the major works of logical extrapolation in several years. . . . a sharp melodrama of power-conflict and revolt which manages . . . to explore all the implied developments of [its imagined] society." Imagination reviewer Mark Reinsberg described it as "a marvellously entertaining story" and "A brilliant future satire.

I must have been in high school when I read both, so I don't remember many plot details of either, and I've never re-read them as an adult. But I do remember that I felt distinctly uneasy while reading them. I was already being programmed by society to be suspicious of anything critical of "The System".

Unlike "Piano", which I recall as gripping, but somewhat depressing, I remember "Merchants" as being very funny, relying more on humour than pathos to get its subversive message across.

Either one makes an excellent antidote to Heinlein's "Starship Troopers".