This part of IEC 62647 is intended for use as technical guidance by aerospace, defence, and high performance (ADHP) electronic applications and systems suppliers, e.g., original equipment manufacturers (OEMs) and system maintenance facilities, in developing and implementing designs and processes to ensure the continued performance, quality, reliability, safety, airworthiness, configuration control, affordability, maintainability, and supportability of high performance aerospace systems (subsequently referred to as ADHP) both during and after the transition to Pb-free electronics. The guidelines may be used by the OEMs and maintenance facilities to implement the methodologies they use to ensure the performance, reliability, airworthiness, safety, and certifiability of their products, in accordance with IEC/TS 62647-1:2012. This document also contains lessons learned from previous experience with Pb-free aerospace electronic systems. The lessons learned give specific references to solder alloys and other materials, and their expected applicability to various operating environmental conditions. The lessons learned are intended for guidance only; they are not guarantees of success in any given application. This document may be used by other high-performance and high-reliability industries, at their discretion.