When you open the "Feature Class Properties" page in Catalog to examine the fields in a feature class, the Field Properties section tells you if the field is controlled by a domain. There's not a convenient way to view a list of the values in that domain, however. You have to close the feature class properties dialog, then open the geodatabase properties dialog and find the domain to view it. It would be far more convenient if there was a button on the feature class properties to view the domain values of the currently selected field.
