The current studies aimed to find out whether a nonintentional form of mood contagion exists and which mechanisms can account for it. In these experiments participants who expected to be tested for text comprehension listened to an affectively neutral speech that was spoken in a slightly sad or happy voice. The authors found that (a) the emotional expression induced a congruent mood state in the listeners, (b) inferential accounts to emotional sharing were not easily reconciled with the findings, (c) different affective experiences emerged from intentional and nonintentional forms of emotional sharing, and (d) findings suggest that a perception-behavior link (T. L. Chartrand & J. A. Bargh, 1999) can account for these findings, because participants who were required to repeat the philosophical speech spontaneously imitated the target person's vocal expression of emotion.