Honorific (respectful) form of 'to come' or 'to go', used when speaking about someone deserving respect.
どうぞ週末はわが家へお越しください。
Please do come to our home this weekend.
部長がお越しになりますので、会議室を整えてください。
The department manager will be coming, so please prepare the meeting room.
先生は来週研究室にお越しになりますか？
Will the professor be coming to the lab next week?
お客様がもうすぐお越しになる予定です。
A guest is expected to arrive soon.