Graham Interpreting screens all of its interpreters. In addition, interpreters have a variety of interpreting credentials. There are state and national certifications. The Registry of Interpreters for the Deaf administers a national examination that tests knowledge of ethics, interpreting skills (both receptive and expressive), and culture. There are also specialized certifications, such as medical, legal, and educational. The more information you provide to the agency, the easier it is for Graham to send an interpreter with the skills and specialty to match the assignment.