A contractor is a person or firm hired to perform construction work. Contractors range from a single electrician to a multinational company building an airport. They sign a contract, agree to a scope and price, and are responsible for delivering the work.

There are many types. A general contractor manages the overall project and hires subcontractors for specialized trades. A subcontractor performs a specific portion, such as plumbing or roofing. A prime contractor contracts directly with the owner. A specialty contractor focuses on one trade.

Contractors are licensed and regulated in most places. Licensing requirements vary, but typically include exams, insurance, and bonding. Bonding protects the owner if the contractor fails to complete the work or pay suppliers.

The contractor's job is not just building. It is estimating, scheduling, hiring, purchasing, and managing risk. Good contractors are organized, communicate clearly, and know how to say no to a bad deal.