Enforce your policies and deal with problems directly. In our company, we have zero tolerance if something prejudicial is said. It's not acceptable. You're better off not to have a policy against prejudice or discrimination than to have one and not enforce it. By allowing prejudice into organizations, we remove our opportunity to grow.
Diversity brings creativity.
A homogeneous group may get along well, but new and different ideas get lost. We need to learn to deal with prejudice in the workplace, to keep it from interfering with being with other people in a productive way. It's important to have perspective about your biases. We need to teach openness in the workplace. Openness is the ability to respect other people's place and position.