Christian Siriano says that 'everyone has a lot to do still' to make fashion more inclusive

At just 22 years old, Christian Siriano became the youngest winner on Project Runway when he earned the title in the series’ fourth season, which aired in 2008. Now, nearly 10 years later, he has become one of the buzziest designers in the fashion industry.

To celebrate, Siriano is launching a new book, Dresses to Dream About. The book gives readers an intimate look into his design process — how he begins each dress with a simple sketch and transforms it into a beautiful “three-dimensional piece,” Siriano tells Yahoo Lifestyle. “I wanted people to see all the work that goes into a dress — it’s a lot.”

Throughout his career, Siriano has dressed magnificent women across film, television, music, and politics, including Gwyneth Paltrow , Viola Davis, Rihanna, Michelle Obama, and Oprah Winfrey, to name a few.

Over the summer, he dressed Leslie Jones for the premiere of Ghostbusters after she voiced her frustration on Twitter about the lack of designers willing to dress her for the film event. Siriano quickly jumped in to offer his help, and the actress stunned on the red carpet, wearing a beautiful crimson-red, off-the-shoulder gown.

But for Siriano, dressing women of all shapes and sizes on the runway and off isn’t anything new. In fact, he has dressed multiple stars who weren’t “the average size.” What is new is that the industry is finally catching on, placing the designer at the forefront of fashion diversity.

“I never thought it would become such a topic,” Siriano shares with Yahoo Lifestyle. But he says he’s happy that it’s allowed designers like him to support “women, people of all different cultures.” At the end of the day, “I think being a good designer is someone who is able to dress a lot of different types of women” — not just sample size, he says.

The designer agrees that fashion is becoming more inclusive. “It’s definitely moving in an amazing direction” and “changing dramatically,” he says. But Siriano points out that “everyone has a lot to do still,” starting with the retailers, and then “other designers need to get on board for it to become a bigger thing.”

However, “the customers are there,” he says. Siriano excitedly shares that “our sales have doubled, tripled, for sizes over 12. That’s pretty amazing. I think anybody who’s running a business should understand that — that’s a good thing.”

Aside from championing diversity on the runway, Siriano still has his own share of hardships. “There’s challenges every day. But I think the challenge is really just hanging in there. … It’s keeping it going, getting the customers excited to come back season after season. That’s the hardest part.”

It’s about finding ways to stay relevant when “fashion changes so quickly.” Especially as a young brand, Siriano says he’s “competing with huge powerhouse companies, but we’re hanging next to them. At the same retailers. That’s such a challenge, to be on par with Dior, but you’re [still] not Dior.” But then on the flip side, the rewarding part is that “I am hanging next to Dior and I am doing it.”

At just 31, the designer has accomplished so much in his almost-10-year career — dressing countless celebrities and forging numerous partnerships with such companies as Lane Bryant, Payless, Starbucks, Nordstrom, and Disney. Now, he has a new book out, but Siriano isn’t ready to slow down.

“We really want to expand the company, grow the business,” he says. In fact, “we’re opening a bigger flagship store early next year and making sure that it is amazing, beautiful, and will be a new place for people to come and shop — a whole different kind of store concept.”

Dresses to Dream About is available now at rizzoliusa.com and retails for $45.

Read more from Yahoo Lifestyle:

? Michelle Kwan on her rule-breaking figure skating style: ‘I was the first person to wear jewels on the ice’
? Social media goes wild for Leslie Jones in thigh-high slit gown: ‘Nice legs, lady’
? Watch Christian Siriano’s awesome embrace of body diversity on the runway: ‘People Are People’

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