IEC TR 63079:2017+A1:2018+A2:2020 gives recommendations for and guidance on the design, planning, installation, testing, operation and maintenance of a hearing-loop system (HLS) intended for communicating speech, music and/or other signals. It is mainly concerned with HLS for hearing enhancement, in which the signals are communicated to users of hearing aids equipped with magnetic pick-up coils. This document does not apply to induction-loop systems which use a carrier frequency, nor to other systems for hearing enhancement purposes which do not use magnetic induction. This consolidated version consists of the first edition (2017), its amendment 1 (2018) and its amendment 2 (2020). Therefore, no need to order amendments in addition to this publication.