PRO stands for Player Referee Organization. It is the standard name given to AYSO Referee programs geared towards kids 18 years old and younger. Anyone is welcome to become a youth referee – they do not have to be a soccer player to join PRO. However, 95% of AYSO youth referees are also soccer players and therefore the program is named Player Referee Organization.
National guidelines state that kids 12 years old and older can become certified Referees (U-5 thru U-8 games) or Regional Referees (U-5 thru U-10 games). Youths under 12 are welcome too, but usually need to join the program as Assistant Referees.
For more info, please contact the PRO directors at firstname.lastname@example.org .