The system involves using signals and locations which have been agreed in advance.
"You both must agree, in advance, to support me if he appeals against my - discipline."
Did the idea never cross his mind that maybe Syria should also agree in advance to land for peace?
The terms of the apology had not been agreed in advance.
You should agree in advance on priorities before getting started.
The priority for the 1990s will be agreeing in advance how to measure the results of a project.
A price is agreed in advance and even if the project takes far longer than initially planned, there will be no extra charge.
Guests usually agree in advance to switch accommodations on a set day.
They might also agree in advance to share all the costs of driving, which could include tickets.
But he would have to agree in advance to a number of stringent conditions.
