It was the South Africans who had requested the meeting to discuss issues relating to interpretations and procedures and the management of the current laws by match officials, after O'Brien had been critical of comments de Villiers made in the media after the World Champions' losses to New Zealand and Australia.
"We are glad we had the chance to meet," said Andy Marinos, South Africa's manager of national teams.
"The meeting was held in a good spirit and we spoke openly about the issues."
O'Brien echoed those sentiments, suggesting that the meeting was beneficial for both parties.
"It was good to meet and discuss areas of concern and going forward we are now much clearer from both sides."
The Springboks and O'Brien agreed that there will be no further comment on the matter.