In the field of interpreting, as in other professions, appropriate credentials are an important indicator of an interpreter’s qualifications. The Registry of Interpreters for the Deaf (RID) awards certification to interpreters who successfully pass national tests. The tests assess not only language knowledge and communication skills, but also knowledge and judgment on issues of ethics, culture and professionalism. An interpreter may hold one or more certifications. Information on certifications is available from RID.
Some common sign language interpreting certifications are:

• CI - Certificate of Interpretation
  
• CT - Certificate of Transliteration
  
• CSC - Comprehensive Skills Certificate
  
• SC:L - Specialist Certificate: Legal
  
• IC - Interpretation Certificate
  
• TC - Transliteration Certificate
  
• CDI - Certified Deaf Interpreter