Forty-six college students provided saliva samples just after taking an examination, one hour and 45 minutes later, and several days later, at a period of rest. As compared with baseline levels, the power stress of an examination was associated with an increase in salivary immunoglobulin A (S-IgA), a measure of B-cell immune function, and with an increase in norepinephrine (NE) concentrations in the saliva. The increase in NE was greater for those for whom n power was greater than n affiliation rather than for those for whom the reverse was true. Greater increases in, and levels of, NE at the examination and after were associated with greater subsequent drops in S-IgA, which reached below baseline levels for those for whom n power was stronger. The examination stimulated adrenergic activity, which in the long run depressed immune function for those with a strong power motive who had been most aroused adrenergically by the examination.