The holiday has become a Christmas classic since its release 18 years ago.

For costume designer Marlene Stewart, the 2006 film’s enduring popularity is just another nice addition to the unforgettable experience of working with the “incredibly talented” cast, including Kate Winslet, Jude Law, Jack Black, Cameron Diaz and Eli Wallach.

“I think for me, one of the greatest joys of being a costume designer is working with these actors, having the chance to work with incredibly talented, interesting and creative (people), a team like this. “It was wonderful,” she tells PEOPLE in an exclusive interview.

“So all in all, it was just icing on the cake that the film has become something of a holiday classic, and luckily I get to watch it over and over again every year,” Stewart adds, noting that she loves being a new audiences to see Discover the film directed by Nancy Meyers via streaming.

“I can’t tell you, even the younger generation, the next generation, everyone says, ‘Oh, The holiday.’ So I’m glad I had the opportunity to work on it and I’m lucky that it comes back every year and you have the chance to experience it again,” says Stewart. “It was so much fun to work on, and that translates to fun.”

“The idea was to create a luxurious and fun look,” explains Stewart. “She is a working woman here. Back then, even though it was 20 years ago, it was about: ‘What do women wear to work? What are the standards? How does that change?’ ”

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According to Stewart, Diaz, 52, and the film’s other stars had input into their characters’ looks. She says that the collaborative dialogue between costume designer and actor on set is incredibly important.

“For many actors and actresses, they find character in their clothing. ,Yes that is correct. No, that is the limit. She wouldn’t do that. Yes, that makes sense. That shows a certain part of her personality,’” Stewart explains. “There is so much feedback. It’s that important. You want (the stars) to feel comfortable.”