(C.H.O.A.M., Combine Honnete Ober Advancer Mercantiles) Acronym for Combine Honnete Ober Advancer Mercantiles –the universal development corporation controlled by the Emperor and Great Houses with the Guild and Bene Gesserit as silent partners.

The Combine Honnete Ober Advancer Mercantiles or CHOAM, essentially controls all economic affairs across the cosmos, although it relies upon the Spacing Guild for transport across space due to the Guild's monopoly on faster-than-light travel.

CHOAM touched almost all products the Guild will transport, from art forms to technology and of course melange.

Many Houses depend on CHOAM profits, and an enormous proportion of those depend on melange.

CHOAM directorships were the real evidence of political power in the Imperium, passing with the shifts of voting strength within the Landsraad as it balanced itself against the Emperor and his supporters. Directorship in the CHOAM was the key to wealth, each noble House dipping from the company's coffers whatever it could under this power. The flag of CHOAM is yellow, blazoned with a circle, half-red and half-black.