[2] Gwaltney studied under Ernie Caceres and Peanuts Hucko, playing clarinet in college bands and while serving in the military.
[2] He then worked with Wild Bill Davison, Billy Butterfield (1958–59), Buck Clayton (1960), Charlie Byrd again (1962–63), and with his own ensembles.
[2] Gwaltney established the nightclub Blues Alley in Washington, D.C.[3] After selling it, he still performed there regularly guitarist Steve Jordan.
He organized the Virginia Beach Jazz Festival and the Manassas Jazz Festival;[2] he led bands at Manassas with Davison, Ed Polcer, Willie "The Lion" Smith, Eddie Condon, Doc Evans, Bobby Hackett, Vic Dickenson, Maxine Sullivan, and Jimmy McPartland.
In 1986 he recorded a tribute album for Pee Wee Russell and gave a concert at the Smithsonian Institution honoring Jimmie Noone.