The present study investigates transfer effects in two groups of German learners of French for ambiguous relative clause (RC) constructions. The first learner group had started to learn French before English, whereas the second group had started to learn English before French. The RC attachment ambiguity is interesting to study possible transfer effects in the learners because attachment preferences have been reported to vary cross-linguistically. Therefore, transfer effects from English to French in the present study were expected. It was found that English-dominant learners of French transfer the attachment preference from English to French. French-dominant learners, in contrast, were not influenced by the English preference. Language dominance was found to be a more reliable indicator for cross-linguistic transfer than length of exposure to a foreign language. (Contains 4 tables and 4 notes.)