This occasional column will address issues — both real and imaginary — that impinge on what I think is the main activity of management science/operations research: building models that attempt to describe the world as it was, as it is, and as it will be. I will write on those modeling matters that I believe are important to the advancement of our profession, that are important to me (and I trust to the readers of Interfaces), and that are important to the general public who support us in our research and applications. I hope that we can better understand how what we do can influence the course of human events. And that the general public can better appreciate our successes and failures and aid us in advancing our science of decision making. Modeling is both fun and a serious business. In this first column, I would like to share with you some of the thoughts and quotes on models that have influenced me.