Tim O'Brien is one of the spearheads of contemporary bluegrass. As co-founder and lead vocalist of Hot Rize, the Grammy-winning singer, songwriter, and multi-instrumentalist served as a bridge between the traditional sounds of the hill country and the modern styles of bluegrass in the 1980s. In addition to his group work, O'Brien has continued to expand the music's borders as a soloist, a producer, and as a duo partner with his sister Mollie. His songs have been recorded by Kathy Mattea, the Seldom Scene, New Grass Revival, and the Johnson Mountain Boys, and his deft guitar picking has set a standard for the instrument's role in bluegrass. In the 2010s, he expanded his boundaries by forming the Tim O'Brien Band, who soared to the top of the bluegrass charts in 2019 with their eponymous debut. His prolific recording career carried into the next decade, most notably with 2023's Cup of Sugar, his first entirely original set.