If a job has a registered agreement, the bonus does not apply. However, a written contract of employment may provide for wages and conditions of employment that go beyond the procurement system prevailing in a given sector or organization. The terms of employment contracts may be modified and updated at any time. A contractual agreement can offer employers and workers the necessary flexibility for the company. Employers are not able to offer workers terms and conditions of employment below the NES. They may, however, insert clauses that improve the provisions of the NES or provide provisions that are more important than those described in the NES. Nevertheless, employers must manage the risks arising from the decision. .