The first High-level Meeting on Transport, Health and Environment was convened by the UNECE and WHO/Europe secretariat on 4 May 2001 to decide on further steps for achieving transport sustainable for health and the environment at the pan-European level. It decided inter alia to rationalize the work on transport, health and environment carried out by UNECE and WHO/Europe under the Vienna (1997) and London (1999) follow-up processes, through consolidation of the international institutional mechanisms and prioritization of the related work.
The second High-level Meeting, held on 5 July 2002, established THE PEP for joint administration under the auspices of UNECE and WHO/Europe. In particular, it decided on THE PEP Policy Framework, THE PEP work plan and the establishment of THE PEP Steering Committee.
The fifth High-level Meeting is being held in Vienna in November 2020.