Employing the framework of emotional contagion, this study investigated the link between group interaction sequences (specifically complaining and interest-in-change messages) and group mood. Fifty-two work group discussions from two German industrial enterprises were coded with the act4teams category system (e.g., Lehmann-Willenbrock & Kauffeld). Lag sequential analysis revealed complaining as well as interest-in-change cycles in the discussion flow. A two-dimension (arousal and pleasure) rating instrument was developed to assess group mood. Results showed that complaining cycles were linked to a passive group mood, and interest-in-change cycles were correlated with an active group mood. Neither complaining nor interest-in-change cycles were correlated with the pleasure dimension. We discuss theoretical, methodological, and practical implications of our findings as well as prospects for future research on interaction cycles and group mood.