This paper examines how bank relationships affect firm performance. An empi
rical implication of recent theoretical models is that firms maintaining mu
ltiple bank relationships are less profitable than their single-bank peers.
We investigate this empirical implication using a data set containing virt
ually all Norwegian publicly listed firms for the period 1979-1995. We find
a robust and economically relevant negative two-way correspondence between
the number of relationships and sales profitability. We also find that fir
ms replacing a single relationship are on average smaller and younger than
those firms choosing not to replace a single relationship.