David Alvin Buchsbaum is an American mathematician who specialised in homological algebra and category theory. He received his Phd from Columbia University in 1954 under the direction of Samuel Eilenberg.
Buchsbaum introduced the notion of exact category in 1955, a notion equivalent to that of abelian category introduced later by Grothendieck in his 1957 Tohuku paper.
His students include Peter Freyd and Barry Mitchel.