The term RPO usually in model railroad circles is thought to stand for Railway Post Office which is correct for a certain time in railway history. Today, I would like to propose a new use to describe one of the fastest growing parts of the hobby. This is the operations side. Operators are constantly trying to be more realistic in their approach to this aspect of modeling the prototype railroads. What do you call these folks? If we have Railway Prototype Modelers then I propose we now use the term Railway Prototype Operators. They are the new RPO.