Michael Porter developed the Five Forces model to analyze industry attractiveness and competitive rivalry. The five forces are the threat of new entrants, bargaining power of suppliers, bargaining power of buyers, threat of substitute products, and rivalry among existing competitors. Porter's model identifies factors within each force that determine its intensity, such as barriers to entry, supplier or buyer concentration, and the level of differentiation among competitors. By analyzing these industry-level competitive forces, companies can understand the underlying drivers of profitability in their industry.