Bill Shull is a Registered Piano Technician (RPT) of the Piano Technicians Guild (PTG) and a member of the Pomona Valley Chapter of the PTG. The Piano Technicians Guild is the only organization in the United States which certifies piano technicians by providing a range of tests - written, tuning, and technical - to determine competency in tuning and repair. There are many ways to learn piano service skills, but only one professional test of basic proficiency.
In addition, the PTG provides ongoing education through conferences and institutes. Bill Shull attended his first PTG conference in 1976 and has attended dozens of conferences and institutes since, including most Annual PTG Institute since 2000.