In economics, what market structure has many sellers offering differentiated products?

In economics, a market structure with many sellers offering differentiated products is monopolistic competition.

This structure combines features of competition and monopoly. Many firms serve the market, and entry is usually possible, but each firm sells a product that differs somewhat through branding, design, location, quality, or service. Because products are not identical, each firm has some control over its own price.

Restaurants, clothing brands, hair salons, and many consumer services are commonly used as examples. Their products compete closely, but customers may prefer one seller over another. Advertising and product differentiation are therefore important.

Monopolistic competition differs from perfect competition, where firms sell identical products and are price takers. It also differs from oligopoly, where a small number of large firms dominate the market. The concept was developed independently by Edward Chamberlin and Joan Robinson in the 1930s.