Thank you for maintaining your interest in the 17th ECHA Conference and for your patience during the decision process that has tried to take all possible aspects of the uncertain times we are all facing into consideration. After a long consultation series the decision was taken to postpone the 17th ECHA Conference to the following dates: 31 August to 3 September, 2021. Please save these dates in your agenda! All submitted, evaluated and accepted abstracts will be considered for the 2021 conference. Authors that have submitted an abstract maintain the interest to present, do not need to resubmit. Registrations that were already paid, will be transferred to the 2021 conference. Should you however decide not to participate, the general cancellation rules and adapted dates will apply for 2021. Well aware of the uncertainties we face and the adaptations needed to the new reality following this pandemic, as well as the effect it has on our social interaction and way of living, we would anyway very much like to believe it possible to meet again without the use of electronic devices. All necessary steps and possible measures will of course be taken for a conference with a “safe&clean” seal and last but not least, we would love to have the opportunity to share our city Porto - the beauty of the Douro river, the history, the gastronomy and culture with all of you. We do look forward to welcoming the 17th ECHA conference in Porto, 31 August to 3 September, 2021. With warm regards: The ECHA 2021 Conference Organisers.