Foisor won four medals at the European Youth Chess Championships in various age categories: one gold (girls U8 in 1996), one silver (girls U16 in 2004) and two bronze (girls U14 in 2003 and girls U18 in 2007). She represented Romania in the European Girls U18 Team Chess Championship in 2004 and 2007, winning three medals: two gold (2004 individual medal, 2007 team medal) and one bronze (2007 individual medal).[1]
Her result at 2007 European Women's Championship qualified her for the Women's World Chess Championship 2008 in Nalchik, Russia. The final armageddon tiebreak game of her first round match against Monika Soćko ended in controversy. Foisor only needed a draw to advance to the next round, and reached a drawn ending with each player having only a king and a knight. Although Foisor ran out of time, the arbiter initially ruled that the game was a draw. Soćko appealed, pointing out that what matters is not whether checkmate can be forced, but rather if it is possible. Soćko won the appeal and advanced to the next round, eliminating Foisor from the event.[3][4]