People.com is reporting that Shelton asked Lambert to marry him on Sunday. Kathy Best, Lambert's publicist, confirmed the news Tuesday.
Lambert tells People the proposal came as a surprise. She says Shelton proposed to her in the woods near her Tishomingo, Okla., home.
She answered yes.
Shelton went old-fashioned, calling Lambert's father, Rick, to ask permission.
It's been quite the year for Lambert. She scored her first No. 1 with "White Liar," won three Academy of Country Music Awards, including album of the year, and now she's marrying her boyfriend of five years.
There's no word on when the wedding will be.
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