A council introduced under Grand Nagus Zek's late reforms, whose approval the Nagus needs for his decisions, ending the absolute rule that had defined Ferengi government.
The Congress of Economic Advisors is one of the changes that transform the Ferengi Alliance at the end of Deep Space Nine. Where the Grand Nagus once ruled by decree, the new body must ratify what he proposes.
It is described in the episode The Dogs of War. Believing that Zek means to name him successor, Quark is horrified to learn what the office now involves: the Congress, taxes on profit, benefits for workers and the aged, and rights for females, all brought in under the influence of Zek's partner Ishka.
Quark declares that his bar will remain the last outpost of the old Ferengi ways. Zek, as it turns out, had meant the job for Rom all along, judging a gentler Nagus better suited to the kinder Ferenginar he and Ishka have built.