Our research suggests that this belief — that a nonwhite person cannot or will not be a legitimate customer — can indeed worsen discrimination in service delivery. In a follow-up study, we emailed nearly 2,000 hotels and made a similar inquiry about local restaurants. But this time, in addition to varying the race of the inquirers, we varied whether they made clear their intention to stay at the hotel. Indeed, making customer status explicit helped reduce discrimination against minority people. These results are in line with the recent incident at Starbucks: We see that service workers do not apply the rule that every person is a potential customer deserving the same level of service.

Achieving consistency in customer service is no easy feat. Good customer service could mean something different to every patron and every employee. As the sociologist Philip Selznick wrote, employees are “wholes,” not just “roles.” This applies to customer service. People bring their whole selves to work — including their unique experiences, backgrounds and world views.

While well-designed racial bias training is certainly a positive step forward and an important public statement, research on the long-term effectiveness of such training is mixed at best. Instead of relying primarily on trainings to remedy bias, if they truly want to transform the way they serve customers, companies need to make structural changes. For instance, they should standardize scripts and provide employees with specific protocols for managing these situations. Such efforts can institutionalize norms of behavior for employees when they interact with customers.

But even before putting new processes in place for employees to follow, companies must systematically assess the current state of their customer service. We encourage businesses to begin by conducting internal audit studies of customer service. Many of the service behaviors we discussed are subtle. To detect bias in these behaviors requires quantifying different aspects of customer service and comparing treatment quality across a range of customers. After all, a store manager may conclude that an employee is doing a great job upon hearing him say “Have a great day!” to an Asian customer but not recognize that the same employee says “Have a great day! You should come back and try our new blonde cappuccino, with soy!” to a white customer. It is only after identifying these disparities that companies can develop targeted interventions to combat biases.

We urge companies not to stop at racial bias training. Structural changes in how service is delivered are necessary. Large corporations especially have the opportunity — and even an imperative — to be part of the solution.