In recent years there has been an increase in research on the acquisition of morphological aspects of a second language (L2). Specifically, a number of studies have been conducted on the acquisition of grammatical gender in the L2. The study reported in this paper investigated the adult L2 acquisition of grammatical gender in German by first language (L1) speakers of Afrikaans, English and Italian, respectively. The aim of the study was to determine how similarities and differences between the L1 and L2 in terms of grammatical gender affect the acquisition of this aspect of the target L2. Two experimental tasks -a picture naming task and a sentence completion task -were designed to determine to what extent the grammatical gender of nouns is accurately reflected on determiners and adjectives. Throughout, the L1 Italian group outperformed the other two groups. Since Italian (like German) expresses grammatical gender on determiners and nouns, while neither English nor Afrikaans does, the results indicate that the acquisition of grammatical gender in an L2 is easier for learners whose L1 also expresses grammatical gender. Specifically, the results provide evidence for so-called "deep transfer" (transfer of abstract grammatical properties) from the L1 to the L2 in this area of L2 acquisition: since the grammatical gender systems of Italian and German are not congruent, the Italian speakers' advantage over the other two L1 groups cannot be the result of simple "surface transfer" (transferring knowledge of the grammatical gender of specific nouns in the L1 to the L2) and must be attributed to deep transfer.