\author{D.J.Benson} \address{Department of Mathematics, University of Aberdeen, Aberdeen AB24 3UE, UK} \author{J.P.C.Greenlees} \address{School of Mathematics and Statistics, Hicks Building, Sheffield S3 7RH, UK} \begin{abstract} We propose a definition of when a triangulated category should be considered a complete intersection. We show that for the derived category of a complete local Noetherian commutative ring $R$, the condition on the derived category $D(R)$ holds precisely when $R$ is a complete intersection in the classical sense. \end{abstract}