Notwithstanding a surge of novel insights into the male/female variable on human behaviour and cognitive functions, the gender factor is still far from being well understood. Pursuing an interdisciplinary approach, informed by neuroscientific research, this study used linguistic and psychological measures to investigate gender differences in the realm of foreign language (L2) proficiency of late learners. The performance of 64 subjects (32 females), matched for age, education and linguistic background, was analysed regarding gender and personality/motivation differences. Results revealed a gender gap in two domains of L2 expertise and cast doubt on the idea of a general female language advantage: male subjects outperformed their female counterparts in phonetic speech imitation ability (pronunciation). An advantage of the women could be found for grammar learning. Results fit the current line of neurolinguistic research on the neural substrates of language. The study revealed that an open-minded, extravert and motivated personality is beneficial to language learning. A conscious and persistent approach can be favourable for grammar learning. We suggest that foreign language teaching should accommodate more to male/female differences and take into account effects of personality and motivation differences.