Apparently the state-of-the-art is to have buttons for every floor to be outside the car, in the lobby. Each person declares their destination with a press; as

Apparently the state-of-the-art is to have buttons for every floor to be outside the car, in the lobby. Each person declares their destination with a press; as cars arrive they display or announce where they'll stop so the right people can board. But elevators are an old technology; so many buttons and such optimal grouping/scheduling were impractical when the current conventions arose. I've been in an office building in New York that uses this system, it's supposedly very efficient in both time and energy, as it should be. BUT, they have had to station an attendant in the lobby to basically operate the system for visitors, since it's just too obtuse for the average elevator passenger.