it could entail the following:
1) inspection of facility to determine all sources of power feeding it and running through it (this could be a walk thru the building or several hours or days of poking around in ceilings etc in a complex building)
2) turning off and making safe unnecessary circuits (circuits to be demo'd might be physically removed from panel or possibly just disconnected from breakers, hot circuits for lighting (temporary or to remain) should be re-identified at panel and sometimes flagged in the ceilings so they don't get cut,
3) feeders and services running through the space and/or to other spaces or not to be demo'd might be tagged or spray painted
4) your guy in the field might have to meet several other contractors to point out items they need to be careful of
5) emergency systems might need to be reconfigured so that standby power systems do not energize circuits in the demo'd area
6) areas could be identified that should be avoided or carefully demo'd to avoid dust in transformers, cutting of embedded lines whose location is not known, areas which should be xrayed prior to demo, etc
7) life safety systems that need to be partially bypassed or dogged need special attention and should be identified, if the area has hazardous locations involved this could be a complicated issue (could involve deactivation of foam systems etc so they don't accidently engage, but are available for manual operation or operation on off-hours automatically etc etc)
8) if the area is especially hazardous, firewatch schedules might need to be set up while some emergency suppression systems are dogged during demo hours, etc
this list could entail a lot more or a lot less - it depends on the job
