Would you translate this as 'general works council' or 'workers council', or something else? The article I'm looking at refers to 'Gesamtbetriebsratsvorsitzende' (presumably the chairman) and later the 'Betriebsrat'...
IATE, a european inter-institutional terminology database (“Inter-Active Terminology for Europe"), offers
Gesamtbetriebsrat: central works council
But i'm sure that "joint works council" as proposed by Takkat is a good match ,too!
This indeed is a very German expression not only that it is composed of long nouns but also as it describes a very special worker's organisation in German companies. Here is my suggestion (from reading translations of various annual financial reports of larger German companies)
Betriebsrat: works council
Gesamtbetriebsrat: joint works council
Gesamtbetriebsratsvorsitzender: chairman of the joint works council