CAUTION: The Sender of this email is not from within Dalhousie. This is the third announcement for the Category Theory 20->21, Genoa (Italy) and online, 30 August to 4 September 2021. Given the current situation of the pandemic in Italy, the event is confirmed in its hybrid form, and it is now possible to register. We understand that the different developments of the epidemic worldwide determine a high level of uncertainty, and make it difficult to plan ahead. Nevertheless, we strongly believe that the scientific communities must commit themselves to relaunch research activities with physical meetings whenever possible. This is why we have engaged ourself in the organization of the conference. On the other hand, we need everybody's help to make it work. *** Registration *** Since there are two ways of attending the conference, we set up two registration tracks. First track: online participants. The conference fee is EUR 30 for regular attendee, EUR 20 for PhD students. It must be paid online by 20 July 2021, 23:59 HST (-10UTC). If you have already decided to attend the meeting online, we kindly ask you to to complete your registration as soon as possible as this will help us organize a better conference. Second track: onsite participants. The conference fee is EUR 130 for regular attendee, EUR 100 for PhD students, and it must be payed online by 20 August 2021, 23:59 HST (-10UTC). The conference fee includes all lunches and coffee breaks. We allow such late registration as we understand you may find it difficult to schedule your dates in August much in advance. On the other hand, you must understand that we need to have a clear idea of the number of participant onsite in order to ensure the highest standard of safety for all. This is why we keep our pre-registration open at the page https://sites.google.com/view/ct2021/registration, and we warmly invite those interested in attending onsite to pre-register immediately. Change track. If you wish to change your mode of participation and you have already registered, please contact the organizers: we shall accommodate your needs. Directions for Registration. Registration is in two steps: 1. If you have not done it, first pre-register at https://sites.google.com/view/ct2021/registration 2. Then pay the conference fee at https://sites.google.com/view/ct2021/registration and email your receipt to info.ct2021@gmail.com with object "Receipt". For specific queries, please write to info.ct2021@gmail.com. Best regards, ORGANIZING COMMITTEE Sandra Mantovani, Giuseppe Metere, Eugenio Moggi, Andrea Montoli, Giuseppe Rosolini (chair) [For admin and other information see: http://www.mta.ca/~cat-dist/ ]