In 1969, she took part in the Grand Prix RTL International with the song "Die Legende der Liebe".

The same year, she reached the single charts again – "Das hat die Welt noch nicht erlebt" peaked at #19.

At the same time, she tried to start a career in France, where she played the lead role in the musical Un enfant dans la ville next to Michel Fugain but only had a couple of popular hits with "L'Autoroute", "Amour toujours", "Je c'est I, Tu c'est you", "L'amour en blue jean" and "Les petits soldats".

[3] After the reprise of the winning song, she was booed off stage[4] and her victory caused a stir in Germany as she was not the winner of the first round of voting and because of her mediocre vocal performance.

[6] She performed the duet "Lady" with David Hanselmann and finished sixth out of the twelve participants, however, the song was commercially the second most successful one of the year.

Mary Roos was blamed for a bad vocal performance which she says was caused by an emotional crisis after her separation from her husband Werner Böhm.

[8] "Aufrecht geh'n" would also be her last appearance in the single charts until 1999, when she released a German cover version of Cher's song "Believe" ("Leider lieb ich dich immer noch").