Imagine you are faced with a moral dilemma. Would you expect your actions to differ depending on whether you are using a native or foreign language? As unintuitive as it may seem, using a foreign language changes our choices. While there is increasing evidence of such foreign language effects in domains ranging from moral judgment to risk taking, little is known about the underlying processes. Utilizing both behavioral and physiological measures, the studies presented here explore potential explanations for why using a foreign language affects the decisions we make. The results from Studies 1-6 suggest that those using a foreign language make more utilitarian moral choices, and that this is due to a reduction in emotional processing rather than an increase in analytical processing. Despite the apparent reduction in emotional processing, Studies 7 and 8 reveal no effects of language on either heart rate or heart rate variability when participants were asked to make risky and consumer choices. These results raise the possibility that foreign language use may dampen affective or heuristic processing without necessarily affecting emotional arousal. Contrary to past results, Study 7 also revealed no effect of language on risk taking, suggesting that foreign language effects within this domain may not be as robust as for moral judgments. Study 8 demonstrated that using a foreign language increases both buying and selling prices during a consumer decision task, potentially due to a reduction in the hedonic value of money. Lastly, Studies 9-12 explored the role of mental imagery for moral and risky judgments and find that using a foreign language results in less vivid visualizations, which partially explain behavioral effects. Taken together, the findings of this project suggest that using a foreign language changes our choices due to a reduction in affective processing, which, in part, results from less vivid mental imagery when using a non-native tongue.