The Oscar winner proposed to pretty Floridian Barroso "shortly before Labor Day (05SEP05)", according to his publicist. No date has been set yet for their wedding.
The Good Will Hunting actor gave the interior designer a "beautiful big diamond ring" he bought from jeweller Alvin Goldfarb in Seattle, Washington, the representative tells American magazine Us Weekly.
Damon, who has dated a series of beauties including Minnie Driver, Winona Ryder and Claire Danes, has not been married before. Barroso has a six-year-old daughter, ALEXA, from a previous relationship.