The cloned humanoid species of Weyoun, Eris, Yelgrun, Gelnon, Borath and others who served the Founders as the administrators of the Dominion, field supervisors of the Jem'Hadar armies, and envoys for client races such as the Karemma. They, like the Jem'Hadar, serve the Founders without fail.
Borath says "The Vorta serve the Founders, in all things." Though created in two genders, they have poor eyesight but excellent hearing.
A Dominion warship crew's Vorta and Jem'Hadar First are typically the only members of the bridge personnel to be allowed access to data and monitor screens, via small holographic eyepieces worn as a headset.