​A to Z Officiating is owned and operated by John Ziello.  John has been in the baseball business for 30 yrs. in the South Bay area.  He has developed relationships with various coaches, league presidents, parents and children while providing professional umpires to the many baseball leagues he services.  John prides himself on integrity both on and off the field.  John’s expects his work ethics of fairness and good character in all of the umpires that represent A to Z Officiating.