This article shows that endoclitics do exist in Udi, a language of the Nort
h East Caucasian family, and this fact poses a challenge to the lexicalist
hypothesis. Clitics may be positioned between the morphemes of complex verb
stems and immediately before the final segments of monomorphemic verb stem
s. The author argues, on the basis of accepted tests for wordhood, that com
plex verb stems are single words, not phrases. On the basis of criteria dev
eloped by Zwicky and Pullum (1983), it is argued that the clitics of Udi ar
e true clitics. An analysis of the placement of clitics in various position
s inside verb stems is proposed in optimality theory. The author shows that
phonological phenomena do not provide an alternative basis for positioning
these clitics and concludes that clitics in Udi are a counterexample to th
e lexical integrity hypothesis.*