A time and materials contract is an agreement used in project management where the client pays for the actual time spent by workers and the materials used in a project. This type of contract is often used when the scope of work is uncertain, allowing flexibility as the project progresses. In this arrangement, the contractor typically charges an hourly rate for labor and adds the cost of materials, plus any additional expenses. This ensures that the contractor is compensated fairly for their work, while the client can monitor costs and adjust the project as needed.