[8] At the age of 15, Sunwoo moved to the United States to attend the Curtis Institute of Music where he received the Rachmaninoff prize and studied with Seymour Lipkin.

On June 10, 2017, Sunwoo won the gold medal of the Fifteenth Van Cliburn International Piano Competition in Fort Worth, Texas, becoming the first Korean to do so.

The quadrennial competition, named in honor of pianist Van Cliburn, included four rounds of performances consisting of two 45-minute solo recitals and one 60-minute solo recital with no overlapping repertoire in addition to a piano quintet performed with the Brentano String Quartet and two piano concertos played with the Fort Worth Symphony Orchestra, one under Nicholas McGegan and other under Leonard Slatkin.

[14] Sunwoo is an active chamber musician and has performed with such ensembles as the Jerusalem (during the final round of the 2014 Vendome Prize Piano Competition held in Verbier) and Brentano String Quartets in addition to violinist Ida Kafavian, cellists Edgar Moreau, Gary Hoffman, and Peter Wiley, and pianist Anne-Marie McDermott.

In 2007, he toured Central America including Costa Rica, Guatemala, and Panama with the Kumho Asiana Cultural Foundation.