Price-cap regulation is a form of incentive regulation capping the prices that firms in a natural monopoly position may charge their customers. Designed in the 1980s by UK Treasury economist Stephen Littlechild, it has been applied to all privatised British network utilities. It is contrasted with both rate-of-return regulation, with utilities being permitted a set rate of return on capital, and with revenue-cap regulation, with total revenue being the regulated variable.[1]