Heidi Klum Calls 18-Year Friendship with Tim Gunn 'the Longest Marriage I've Ever Been in'

Team work makes the dream work, and for Heidi Klum and Tim Gunn, they are proving to be the fashion world's ultimate "power couple."

During a Tuesday appearance on TODAY with Hoda & Jenna, the 49-year-old supermodel and TV personality teased that Gunn is practically her husband at this point. The pair have been collaborating on projects since their days on fashion competition show Project Runway, which made its television debut in 2004.

"I always say we're the longest marriage I've ever been in," she said as she smiled at Gunn and grabbed his hand.

"And for me too," Gunn agreed, with the Emmy winner adding, "and for 18 years."

When asked by Jenna Bush Hager what makes their work relationship flow so well, Klum turned back to Gunn and jokingly said, "possibly because I only understand every third word you say. He gives me all these amazing words like 'titillating' and I don't know. You have like this dictionary of [words]."

"It's my many years as a teacher," the 68-year-old replied. Gunn served on the faculty of Parsons School of Design from 1982 to 2007.

"But really Jenna, I think the fact that we're in many ways so different – and in many other ways so much alike – is part of what holds us together. And we really love and respect each other."

"And we love what we do," the supermodel added, to which Gunn agreed.

Klum and Gunn are currently promoting Season 3 of their latest fashion competition show Making the Cut, and fashionistas should get excited because it sounds like their best season yet.

"I would say it's the best crop of designers we've ever had," Klum said on TODAY with Hoda & Jenna. "So we have 10 designers from all around the world and they're battling it out for one million dollars. I think the only other competition show that I know is America's Got Talent who has a million dollar price tag at the end." Klum stars as a judge on that popular hit show as well.

"It's just so amazing for these designers who actually already have careers, but it gives them that extra push because with a million dollars you can do a whole lot for your business," she continued.

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And while Klum and Gunn may have one of the strongest bonds ever, Klum is already a married woman, after announcing her engagement to Tom Kaulitz back in December 2018. The mother to daughters Lou, 10, and Leni, 15, and sons Johan, 12, and Henry, 14 — and the Tokio Hotel musician, 29, first sparked dating rumors in March 2018 after they were spotted kissing on set while she was filming America's Got Talent.

TMZ reported they tied the knot the following February, just two months after Kaulitz proposed.

"He is the kindest, sweetest, most caring, loving person. I feel so lucky. I don't know the last time I was this happy in my life," Klum told PEOPLE. "He is absolutely wonderful. Maybe it is because he is German and we understand each other in a different way. But so far so good."