Sonia Sotomayor has been sworn in as the first Hispanic justice on the United States Supreme Court.
She is only the third woman to sit on the court.
On Thursday, the Senate voted 68-31 to approve her with 59 Democrats and nine Republicans voting in favour.
The Supreme Court is the highest court in the United States, with the power to strike down unconstitutional laws. Once appointed, justices serve for life.
They are nominated by the president, but must receive approval from a majority of senators before they can take up their post.
Justice Sotomayor, 55, was sworn in by Chief Justice John Roberts at a brief ceremony that was the first one open to television cameras in the court's history.
Standing next to her mother and brother, she pledged to "faithfully and impartially" discharge her duties.
The BBC reports the public ceremony followed a private one minutes earlier in which she promised to support and defend the constitution.
During her confirmation hearing before the Senate Judiciary Committee, she was asked repeatedly about a speech in which she remarked that "a wise Latina woman with the richness of her experiences would, more often than not, reach a better conclusion" than a white male judge.
Critics said the remark could have been perceived as racist, but she maintained the comments had been an attempted "play on words" that "fell flat".