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.