Often used for more skilled and managerial posts. They tend to specialise in particular types of job or profession, such as secretarial, computing, accounting and teaching. As with job centres, they keep a list of potential candidates on file who they refer to the employer if a suitable vacancy arises. The agency will often carry out the full selection procedures on behalf of the employer, thus saving the employer a considerable amount of time short-listing and selecting candidates. In return for their services, the employer pays a fee to the agency. Despite this fee, the use of commercial employment agencies may prove to be a cheaper method than advertising on a national scale.