Artists like Nickel Creek, Garth Brooks, and The Dixie Chicks have covered his songs and he has collaborated with the likes of his sister Mollie O'Brien, his wife Jan Fabricius, Steve Earle, Dirk Powell, Dan Auerbach, Sturgill Simpson, and Mark Knopfler, who described him as "a master of American folk Music, Irish music, Scottish music - it doesn't matter; a fine songwriter and one of my favourite singers."
Living in Nashville since 1996, his skills on guitar, mandolin, fiddle, and banjo make him an in-demand session player, and he was inducted into the West Virginia Music Hall of Fame in 2013 and into the Colorado Music Hall of Fame in 2022.