In 2001, Professional Stamp Experts presented to the philatelic community a grading system for United States Postage Stamps. It was both bold, and controversial. For the first time, all attributes of a stamp - centering, soundness and eye appeal - were incorporated into a single grading model, and a method for arriving at a single net grade for a stamp was outlined.

In the ensuing two years, we have discussed our model with many of the nation's leading dealers and collectors. We have examined and graded over 20,000 stamps, and carefully observed where our system worked, and where improvements were needed. If there were inconsistencies, we made changes.

In the spring of 2002, we began publishing The Stamp Market Quarterly, a guide to the retail market value of the most collectible U.S. stamps. A year later, we noted the advent of The Scott Valuing Supplement that utilized a similar format to list prices for stamps in six grades. It has been a productive couple of years.

The spring and summer of 2003 has witnessed an expanding interest and discussion of the subject of grading. Why this is happening is obvious. A consistent, logical and understandable grading system is both needed by the market and long overdue.

This booklet will examine the why and how of U.S. stamp grading, and present our current model for fairly and impartially evaluating single U.S. stamps and coil pairs. We do not at present grade pairs or blocks of sheet stamps, coil strips of three or more stamps, covers, proofs or essays. As in the past, we remain open to input and constructive criticism from the philatelic community.