The actress famous for her roles in "Friday Night Lights" and "Nashville" on Wednesday became the agency's tenth such ambassador, joining actor Antonio Banderas, tennis star Maria Sharapova and a handful of soccer stars.
Britton calls her appointment as goodwill ambassador "one of the greatest opportunities of my life."
She plans to focus on poverty eradication, with emphasis on women's issues. She pointed out that women do 66 percent of the world's work but make just 10 percent of the world's income.
Her experiences abroad include studying Chinese in Beijing and traveling to Africa for documentary work and to adopt her son, Yoby, from Ethiopia. She says China was a turning point in her life.