In a recent "Sunday Routine" column in The New York Times, he revealed the dedicated work ethic that got him there.
The secret to Posen's success? He only allows himself one sleep-in day a week.
Even then, he ends up working most of the day.
"I wake up at 8:15, because it’s my one sleep-in day," Posen told John Leland at The Times. "I loll in bed until 8:30, then do a walk with my dogs around Canal Street and lower SoHo."
Once he reads the newspapers, he spends most of his Sunday in the office and checking out retail stores in Manhattan to identify trends.
His ambition helped him gain success at a young age.
Posen launched a fashion label his first year out of college, and has since become one of the most exclusive designers in the industry.
He's also set to become a judge on Project Runway.
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