The effect of second language experience and vocabulary ability was investigated in a semantic priming experiment with weakly related English word pairs (e.g., city–grass). Participants made lexical decisions to targets preceded by unrelated or weakly related primes or to nonword targets preceded by words. Reliable priming was found for monolingual participants; participants who had acquired a second language showed either marginal or nonreliable effects. A similar pattern of results was found with the analysis of vocabulary ability. Only participants with the greater vocabulary ability showed a priming effect. Although previous research has shown that participants with a broad range of linguistic backgrounds demonstrate the typical semantic priming effect (e.g., green–grass) with strongly associated word pairs (Devitto, Burgess, & Decker, 2002), weaker relationships seem to require an extensive contextual history for retrieval.