Standard employee (and contractor) agreements are core to enforcing a security policy at your organization. Your employee agreement sets the terms for your workforce’s employment which ensures all parties have an understanding of how employment starts and ends. Specifically, stating how employment would be terminated is important in the event of the worker not adhering to your policies.
Your customers want to ensure that organizations they entrust with their data ultimately have policies that can be enforced, the last lines of enforcement being the terms of their employment.
Generally the expectation is that before beginning work all workers, employees and contractors, must accept your employee agreement. The agreement should clearly state your organization’s expectations that they adhere to policy and the result of not doing so results in disciplinary action which could lead to termination of employment.
In more mature organizations, auditors will expect that employment agreements are reviewed and accepted on some regular basis (e.g. every 3 years.)