Book excerpt: ARP4761A and its EUROCAE counterpart, ED-135, present guidelines for performing safety assessments of civil aircraft, systems, and equipment. They may be used when addressing compliance with certification requirements (e.g., 14 CFR/CS Parts 23, 25, 27, and 29 and 14 CFR Parts 33, 35, CS-E, and CS-P). ARP4761A/ED-135 may also be used to assist a company in meeting its own internal safety assessment standards. While the safety assessment processes described are primarily associated with civil aircraft, systems, and equipment, these processes may be used in many other applications. The guidelines herein identify a systematic safety assessment process, but other processes may be equally effective.