Professor Mark P. Del Mastro’s essay “Sigma Delta Pi and the AATSP: A Shared Century of Leadership and Collaboration” has been published in the March 2019 issue of Hispania. This “Special Note” connects to Dr. Del Mastro’s ongoing research for his book Sigma Delta Pi: Rediscovering a Century (1919-2019) that will be published by Juan de la Cuesta Hispanic Monographs in 2020.