Rule reminder

In formal Italian: 'Lei' (with capital L) is the standard formal singular address in modern Italian business and professional contexts. 'Voi' (plural) addresses multiple people, but 'Voi' as singular was historically used in fascist Italy and is still found in some southern Italian and traditional commercial contexts. 'Tu' is informal. Bureaucratic Italian always uses Lei (singular) or Voi/Loro (plural formal).