In the previous recipe, you used AWS Control Tower to automatically create your landing zone. AWS Control Tower relies on AWS Organizations to manage Organizational Units and Accounts, so it's very important to understand how it works. In this recipe, you will use AWS Organizations to create your own account structure from scratch, starting with a new master account.

All accounts that use AWS Organizations for billing and control purposes must have a master account. This account controls membership to the organization and pays the bills of all the members (someone's got to do it!).