Following three midair collisions at major general aviation airports in Australia between February and July 2002, the Australian Transport Safety Bureau (ATSB) conducted a review of midair collisions in Australia between 1961 and 2003. The objectives of the review were to identify common characteristics and contributing factors, assess whether there had been a change in the midair collision rate in recent years, and to compare the characteristics and rate of midair collisions with those of other countries.