Employment is a contract between two parties, one being the employer and the other being the employee. An employee may be defined as: "A person in the service of another under any contract of hire, express or implied, oral or written, where the employer has the power or right to control and direct the employee in the material details of how the work is to be performed." Black's Law Dictionary page 471 (5th ed. 1979).

In a commercial setting, the employer conceives of a productive activity, generally with the intention of generating a profit, and the employee contributes labour to the enterprise, usually in return for payment of wages. Employment also exists in the public, non-profit and household sectors. To the extent that employment or the economic equivalent is not universal, unemployment exists.