The article explores how knowledge influences how companies are structured. It introduces a new way to categorize firms based on the types of knowledge they use. The authors show how laws like patents and trade secrets help firms protect their knowledge. Different types of firms, like mass production, high tech, and law firms, organize their decision-making and ownership structures based on their knowledge needs. For example, stock options in high-tech firms help retain knowledge. The authors suggest that policies should consider how firms allocate knowledge to improve their structure.