Launching a startup without addressing key legal fundamentals is like building a house without a foundation — it may stand for a while, but it will eventually collapse under pressure. William Green at Green & Partners has counseled hundreds of founders through the early stages of their businesses and has seen the consequences of overlooking legal essentials firsthand. This checklist covers the ten legal must-dos before launch: choosing the right entity structure, registering your business name as a trademark, drafting a founders' agreement, establishing IP assignment agreements, setting up proper employment agreements, securing necessary licenses and permits, implementing data privacy policies, creating consumer-facing terms of service, setting up a cap table, and obtaining appropriate insurance. Each item is explained with practical guidance and real-world examples of what can go wrong when these essentials are ignored.