Time And Materials Billing (T&M) is a type of payment method in which the client is charged for both the hours worked and the materials used on a given project. It’s an effective way to manage projects with variable costs and timelines since it gives both parties greater flexibility throughout the process. With T&M billing, clients can retain complete control over the scope of their project without having to commit to a fixed-cost contract. This makes it an ideal solution for projects that require agile development or have unknown complexities that might arise as they progress.