Del Day, the Curators’ Professor Emeritus of Missouri University of Science and Technology, discusses his work in the field of bioglass. Day, a past president of ACerS, has spent several decades researching bioceramic and bioglass materials, and developing applications for those materials. He is best known for his work in creating glass microspheres that can be used to encapsulate and deliver tiny amounts of radioactive materials. The Mo-Sci Corporation, a company Day founded and still leads, manufactures these microspheres. Today, the Cleveland Clinic and other leading medical facilities use Mo-Sci microspheres for the treatment of liver and other cancers.