FAA Order 8110.37(), Designated Engineering Representative (DER) Handbook, is a handbook of procedures, technical guidelines, limitations of authority, tools, and resources for Designated Engineering Representatives (DERs), who are appointees of the Federal Aviation Administration.

Both DERs and the FAA offices managing them have individual and mutual roles and responsibilities in the certifications of safety of aircraft and aviation systems.

However, such approval requires comprehension of volumes of complex technical data by a large staff of engineers.

These persons are recognized as Designated Engineering Representatives and are employed by manufactures or consultancies — they are not FAA employees.

[13] One task of DERs is to review technical data for compliance with FAA airworthiness requirements and governing regulations.