Virtual participation to AM'21 is free for everybody with exception of at least one of the presenting authors. For presenting authors the fee is 50 euro. There is no early bird or discount for students. However, thanks to the contribution of our sponsors, a number of fees (at least 4) will be waved for first-authored contributions of master and PhD students of the Third World or anybody in financial problems. Those requesting to have the fee waved, upon acceptance of their contribution need to send their CV to the diversity and equality chairs (maria.mannone@unive.it, maddalena.murari@unipd.it), who will rank the requests on the basis of the excellence of the CVs.