The field of psycholinguistics has long documented how communicating in a second language (L2) can be more challenging than communicating in a first language (L1) because of factors such as low L2 proficiency, accent, and L1 versus L2 differences in the appreciation of semantic or pragmatic nuance (e.g., the emotional connotations or words). Moreover, given that language performance is a primary medium through which people both express their personality and evaluate the personality characteristics of others, these differences in bilingual language processing have important consequences for real-world social interaction. Accordingly, when bilinguals interact with others in their L2, they stand the chance of being misunderstood or misjudged partly because of L1 versus L2 communicative challenges, which can have high-stakes consequences depending on the particular social setting in question. In this article, we selectively review the psycholinguistic literature pertaining to L2 proficiency, emotion, and personality, and apply this knowledge to how communicative effectiveness may be reduced in real-world medical and legal settings. We conclude that increased awareness of these phenomena, and the reasons behind them, can help professionals in the health and legal systems more effectively interact with nonnative speakers. We hope that such increased awareness will lead to the provision of higher quality services to bilingual people.