There is no system-driven process to subscribe alums who meet a certain criteria to a Space. We have set up multiple class spaces, such as "Class of 1982" and subscribed all alums who meet that criteria AND for whom we have an email address, to the Space. However, when an alum for whom we do not have an email address later adds hers, she is not automatically subscribed to that Space. Thus we have to set up a manual process for once a month, hitting the "subscribe" button in the back end of Spaces for that Space just to ensure that all classmates are subscribed. We are using the Class Space as the primary means for Class Reps to connect with their classmates (YEAH NO MORE EXCEL SPREADSHEETS to 70 classes...), thus we have to maintain the Space(s) as we engage more "lost alums" for each class (i.e. get them to activate their profiles and give us the email address, or the class rep tracks down the email address and sends it to me).