The Paediatric Rheumatology INternational Trials Organisation (PRINTO) is a not for profit, non governmental, international research network founded by Alberto Martini and Nicolino Ruperto in 1996, and initially included 14 European countries (59 countries, 490 centres worldwide with 1189 members in 2014), with the goal to foster, facilitate and co-ordinate he development, conduct, analysis, and reporting of multi-centres, international clinical trials and/or outcome standardisation studies in children with paediatric rheumatic diseases (PRD).