Its all safe and very well choreographed. They go off in waves. Up to 800 balloons some years. ABQ is famous for the ABQ Box in the mornings. When balloons take off they drift north and as they rise they usually hit a southerly wind and head back towards the south. The balloon above must yield to any balloon below as the balloon below can't see the balloon above due to the size of the balloon envelope (flying blind while rising basically). Their are hundreds of "Zebra's" that control the ascension and make sure the air is clear above at takeoff. There have been accidents of course but they are usually inexperienced pilots doing dumb things like trying to land near power lines with too high of wind and they drift into them.