This document, which amends and supersedes WP.29/690/Rev.1 as amended by WP.29/2018/166, contains the Terms of Reference and Rules of Procedure of WP.29. WP.29 shall initiate actions aiming at harmonization or development of technical regulations adapted to technical progress for worldwide acceptance, directed at improving vehicle safety, protecting the environment, promoting energy efficiency and anti-theft performance, providing uniform conditions for periodical technical inspections, and strengthening economic relations. WP.29 shall develop measures on adaptation of legal instruments, foster reciprocal recognition of approvals and certificates, serve as specialised technical body for relevant Agreements, foster worldwide participation, encourage adoption of harmonized technical regulations, develop coordinated work programmes, create working environment facilitating Contracting Parties’ obligations, and ensure openness and transparency. Participants include ECE member countries that are Contracting Parties to listed Agreements, REIOs, and organisations in consultative capacity. Sessions are held at dates fixed by ECE Executive Secretary, ordinarily at UNOG. Provisional agendas are drawn up by Secretariat in consultation with WP.29/AC.2. WP.29 elects Chairperson and Vice-Chairperson(s) at end of last session annually. Each participant has one vote; decisions are made by majority of participants present and voting.