When running buss wires, do you have to run both hot and ground?

"Bus" wires, for Heaven's sake, "bus." Not "buss." The big wide smokey thing that you get stuck behind in traffic is a bus. It carries a lot people. A busboy carries a lot of dishes back to the kitchen. In electrical parlance, a bus (also known as a "bus bar") carries a lot of electrical current, relatively speaking.

The persistent confusion about this probably derives from "Buss" fuse, which is a brand name belonging to the Cooper Bussman company. It is often a good idea to protect your circuit from overcurrents by inserting a Buss fuse between the power source and your bus.

"Bus" in the sense that we are using here is singular. According to the Oxford English Dictionary, the plural (more than one bus) is "busses" as in a fleet of busses; although more and more frequently one sees "buses." In these austere times, it may be prudent to conserve our precious esses.

A buss is a kiss; a Buss is a fuse; and a bus is a heavy-duty wire that carries electricity.

No need to heed to me on this, but it often pays to listen to lionelsoni, and not go around kissing bus bars.