Proceedings index of the Fourth International Congress of CiiEM: Health, Well-Being and Ageing in the 21st Century, held in the Egas Moniz University Campus at Monte de Caparica, Portugal, from 3–5 June 2019.This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/ licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.info:eu-repo/semantics/publishedVersio