Olympic chief Jacques Rogge has told the BBC he expects more positive dope tests in Athens than in Sydney in 2000.
He said testers would follow the lead of the 2002 Salt Lake City Winter Games which saw a big rise in positive tests.
"Each positive case is a victory. It eliminates a cheat and sends a message to those who want to cheat," he said.
"In 2002 we had seven positive tests as opposed to five in the previous 18 Games. We might see the same effect in Athens, and I won't be sorry."
Rogge said he was not "shy of positive cases", adding that the infamous Ben Johnson failure following the 100m at the 1988 Seoul Olympics was "fantastic".
"It was a very important day because it was the beginning of out-of-competition testing and a new resolve for the fight against doping," Rogge said
In a speech to the International Olympic Committee on Monday night, Rogge said that if the number of positive tests did not rise, it would be seen as a sign that testing procedures were not strict enough.
"The news recently has been marked by a growing number of positive doping cases," said Rogge.
"Paradoxically, this is an encouraging sign that the fight against doping is gaining ground, and that it is becoming increasingly hard to cheat.
"Let us continue together to increase education, prevention and punishment, with additional doping controls and more scientific research.
"As it did in Salt Lake City, the IOC has substantially reinforced its anti-doping measures in Athens.
"We have doubled the number of testers and the more we can target the cheats, the more effective we become.
As the countdown to the Games entered its final days, he also paid tribute to the organisers, who had silenced their doubters to get the facilities finished in time.
"We have confidence in our Greek friends to organise excellent Games, which will mark their return to their roots and have already left a remarkable urban legacy," he said.
Rogge also gave his backing to Greece's $1.5bn (£800m) effort to combat the threat of terrorism at the Games.
"These efforts are justified as, going beyond the Games, what is at stake is protecting society, democracy, civilisation and freedom," he said.