This document discusses key aspects of business models. It defines a business model and explains the importance of designing a winning business model. A good business model aligns with company goals, is self-reinforcing through virtuous cycles, and is robust. The choices a company makes in its business model around policies, assets, and governance have consequences that can be flexible or rigid. The Ryanair case study is used to illustrate how its business model choices helped it become a leading low-cost airline carrier in Europe. The relationship between strategy, business models, and tactics is also explained.