Comaneci won three gold medals, a silver and bronze
Planning errors and strikes caused construction costs to spiral and the Montreal Games got underway with building cranes still in place.
Security was high after the terrorist attack in Munich, but once again there were a number of nations absent.
A total of 24 of the 116 registered teams boycotted the Games.
That included 22 African countries who stayed away because of New Zealand's participation, after the Kiwi rugby team had played in South Africa.
Olga Korbut found herself upstaged in gymnastics by 14-year-old Romanian Nadia Comaneci.
Comaneci scored a total of seven maximum 10.00 marks on her way to three gold medals, a silver and a bronze.
On the track, Lasse Viren of Finland successfully defended his 5,000 and 10,000m titles while Cuban Alberto Juantorena won both the 400m and the 800m.
The United States and East Germany dominated the swimming events with Britain's David Wilkie one of only two competitors to break their stranglehold.
Wilkie won the 200m breaststroke in a new world record.