A spread of the activities of a firm or a country between different types of products or different markets. Practically all firms are diversified to some extent: the truly single-product firm is highly exceptional, and even it may supply various markets. Even very small shops usually sell a range of products. The advantage of diversified markets is that a firm or country will be less risky, as its markets are unlikely all to slump at the same time. A disadvantage of diversification is that every product and every market demands slightly different expertise; too wide a range may overstrain the capacity of management, leading to expensive mistakes when managers operate outside their area of competence.

• Lucas critique
• lumpiness
• lump of labour
• lump-sum tax
• luxury
• M0
• M1
• M2
• M3, M4, and M5
• M3, sterling
• Maastricht convergence criteria
• Maastricht, Treaty of
• macroeconomics
• maintenance
• majority shareholder
• maker, market-
• Malthusian problem
• managed currency
• managed floating exchange rate
• managed trade
• management
• management accounting
• management buy-out
• managerial theories of the firm
• mandatory spending programme