Historically, the pharmaceutical industry has been a leader in financial performance and value creation. In recent years, however, its stock-market record has raised doubts about the sustainability of that history along with fundamental questions about the industry’s health. From December 2000 to February 2008 the top 15 companies in the industry lost roughly $850 billion in shareholder value, and the price of their shares fell from 32 times earnings, on average, to 13.

A version of this article appeared in the May 2008 issue of Harvard Business Review.