The structure of the preverb + stem combination is superficially similar in Georgian, a member of the Kartvelian (South Caucasian) family, and in unrelated Udi, a member of the Lezgian group of the North East Caucasian family. Compare (1) and (2) in this regard. (1) Georgian: mi-v-i-t’an-e thither-1sg-cv-carry-aor ‘I took it (away)’2 (2) Udi: ta-zu-š-er-e thither-1sg-carry-er-aorII ‘I took it (away)’ Of interest here is the fact that in both languages the preverb (mi-, ta-) forms a semantic whole with the verb root (-t’an-,-š-), yet an agreement marker (v-, -ne-) occurs between them. This kind of interruption of a semantic and formal unit is a well recognized problem in linguistics (see, for example, Ackerman and Webelhuth 1998). In this paper it is shown that two quite different histories led to the situation found today and illustrated in (1–2).