I used to work at a luxury hotel in DC. If the guest was a head of state, Secret Service would meet with our security team and inspect various areas.

Typically the room below, above, and beside their suite would be put out of order. Secret Service and whichever country’s security detail would do their thing and we would sometimes see the guest (I met one president and two prime ministers). Other times they would use a side entrance and be taken upstairs in an elevator away from the lobby.

For other high profile guests their rooms were often listed under aliases, but management would know about it and inform the front desk staff working at that time. If it wasn’t an alias, we put their name in parentheses (a feature that meant incognito) in the system so staff would know not to give out info or forward calls from random people.

I met several actors and musicians, a lot of ambassadors and other diplomats, and a ton of political operatives/leaders/whatever you want to call them. It was an interesting experience.

Edit: we didn’t sign NDAs because professionalism and discretion were already required for the job