Born to Maronite Catholic
parents in Beirut, Saab is self-trained. He started sewing as a child and knew that one day he would make a living out of it. In 1981 he moved to Paris to study fashion, but ended up returning and opening his workshop in 1982. In 1997 Saab was the first non-Italian designer to become a member of the Italian Camera Nazionale della Moda, and in 1997, showed his first collection outside Lebanon in Rome. In 1998, he started ready-to-wear in Milan, and in the same year, he held a fashion show in Monaco which was attended by Princess Stéphanie of Monaco.
He became an overnight success after he became the first Lebanese designer to dress an Oscar winner, Halle Berry, in 2002. Berry wore a burgundy gown by Saab to the 2002 Academy Awards when she won for Best Actress. Berry later wore another dress by Saab, this time a gold dress, to the 2003 Oscars.
In May 2003, the Chambre Syndicale de la Haute Couture invited him to become a member, and he showed his first haute couture collection in Paris in July 2003. His first ready-to-wear collection in Paris was the Spring-Summer 2006 collection, and Paris is now his permanent ready-to-wear runway.
His creations can be found all over the world, with boutiques located in Beirut, Paris and London (Harrods).
Saab has dressed notable celebrities such as Beyoncé, Aishwarya Rai , Anna Kendrick , Christina Aguilera, Catherine Zeta-Jones, Queen Rania of Jordan Angelina Jolie, Celine Dion, Elena Anaya, Elsa Zylberstein and Victoria, Crown Princess of Sweden.