In the Windows 2000 operating system, a Group Policy Object (GPO) is a collection of settings that define what a system will look like and how it will behave for a defined group of users. In the Windows 2000 operating system, a Group Policy Object (GPO) is a collection of settings that define what a system will look like and how it will behave for a defined group of users. Microsoft provides a program snap-in that allows you to use the Group Policy Microsoft Management Console (MMC). The selections result in a Group Policy Object.