Following weeks of speculation, Lopez announced the news of their engagement in an interview with Diane Sawyer on ABC's Primetime, which will air Wednesday.
"Are you engaged?" Sawyer asked. "Yes," replied Lopez.
"It was very, very beautiful," she added.
She showed Sawyer the infamous ring--a pink diamond solitaire Affleck had custom made by Harry Winston.
The two met last year on the set of the romantic crime comedy Gigli, which is set for release May 9, 2003. At the time, Lopez was married to dancer Cris Judd, her second husband. Lopez filed for divorce from Judd in July, citing irreconcilable differences. Lopez and Affleck cannot wed until her divorce to Judd is finalized in late January, fueling rumors of a Valentine's Day ceremony.
When asked how she and Affleck plan to juggle their hectic Hollywood schedules, Lopez replied, "We have the next, almost, year planned out already if, like, what he's doing, what I'm doing, where we're going to go with each other, who's going not to work at this time. … You really have to plan your life that way if you want to have a relationship in this business."
"We've talked about this so many times and we talked about how people kind of see him with one type of person and me with another type of person, and the two of us together is like, 'How did that happen?' and how we're probably more alike and from the same kind of background and, you know, same kind of upbringing and same kind of family and same kind of house," she told Sawyer.