The author analyzes the strengths and weaknesses of Total Quality Management and Self-Managed Teams, as compared to mass production approaches to service delivery, among customer service and sales workers in a large unionized regional Bell operating company. Participation in self-managed teams was associated with a statistically significant improvement in self-reported service quality and a 9.3% increase in sales per employee. When combined with new technology, teams boosted sales an additional 17.4%. These effects persisted over time. Total Quality Management, by contrast, did not affect performance. This study represents a “strong test” of the efficacy of teams because theory predicts weak outcomes for self-managed teams among service and sales employees in establishments where technology and organizational structure limit opportunities for self-regulation, the nature of work and technology do not require interdependence, and downsizing creates pervasive job insecurity – conditions found at the company studied here.