O'Reilly founded the Association for Research on Mothering (ARM) at York University, that evolved into the Motherhood Initiative for Research and Community Involvement (MIRCI) in 2010. She is founder and editor-in-chief of the Journal of the Association for Research on Mothering, now the Journal of the Motherhood Initiative for Research and Community Involvement. In 2006, as director of ARM, she founded Demeter Press, the first feminist press on motherhood. As well, she is founder of the feminist mothers group "Mother Outlaws".[1]