This article reports the results of an experiment on production of his/her in English as a second language (L2) by proficient native speakers of Italian, Spanish, and Dutch. In Dutch and English, 3rd person singular possessive pronouns agree in gender with their antecedents, in Italian and Spanish possessives in general agree with the noun they accompany (possessum). However, while in Italian the 3rd person singular possessives overtly agree in gender with the possessums, in Spanish they lack overt morphological gender marking. Dutch speakers were found to make very few possessive gender errors in any condition, Spanish and Italian speakers, on the other hand, behaved like Dutch speakers when the possessum was inanimate, but made more errors when it was animate (e.g., his mother). Thus, even proficient L2 speakers are susceptible to the influence of automatic processes that should apply in their first language alone. The pattern of results has implications for pronoun production and models of bilingual language production.