The social identity approach is used to demonstrate how personal and organizational identity is affected by emotions at work and that organizational identification can function as a valuable resource in coping with stressors. We analysed data from an experiment with 96 call centre agents to investigate relationships between positive and negative emotions, identification and strain. Positive and negative emotions were induced by simulated customers who either behaved in a friendly or a rude way. Organizational identification was assessed with a questionnaire, and personal identity salience was measured using video data by counting how often agents said ‘I’ during conversations. Strain was measured through self-reports of emotional dissonance and by assessing immunoglobulin A (IgA) concentration in participants' saliva. Results showed that organizational identification was higher in conditions with positive emotions and was reduced by the induction of negative emotions. Moreover, organizational identification functioned as a buffer against stress: emotional dissonance generally was lower for participants with high organizational identification; IgA levels were negatively associated with organizational identification when agents communicated with unfriendly customers. Conversely, personal identity salience was induced by negative emotions and did not make a positive contribution to the coping process. Copyright © 2011 John Wiley & Sons, Ltd.