Employee monitoring by employers is a kind of personal data processing, and as such, it should be conducted in a transparent and legal manner. Employers should respect personal privacy and avoid violating individuals' basic legal rights, freedom and security. They should also adhere to the principle of good faith (see Articles 2 and 5). The legitimacy of monitoring depends on the purpose, method and scope of monitoring. Within their scope of business or responsibilities, employers may decide to monitor all employee activities for managerial and operational purposes; and such purposes are legal. In order for their monitoring methods to be legal, the methods must be what the purposes necessitate. The manner in which monitoring is conducted must be made public to the employees. Secret monitoring is not allowed, except in criminal and disciplinary investigations. Scope of monitoring must be limited to work-related activities, with a view to reducing personal data collection and processing to the minimum.