The pediatric rheumatic diseases (PRD) are rare conditions associated with important sequelae on the quality of life and long term outcome. The research aimed at studying new therapeutic approaches is difficult because of logistic, methodological and ethical problems. To face these problems 2 international networks; the Pediatric Rheumatology Collaborative Study Group (PRCSG) and the Paediatric Rheumatology International Trials Organization (PRINTO) have been founded. The 2 networks have the goal to promote, facilitate and conduct high quality research for the PRD. In particular they have been able to standardize the evaluation of response to therapy in juvenile idiopathic arthritis (JIA), juvenile systemic lupus erythematosus, and juvenile dermatomyositis, to draft clinical remission criteria in JIA, and to provide cross-cultural adapted and validated quality of life instruments like the Childhood Health Assessment Questionnaire, and the Child Health Questionnaire, into 32 different languages. In this paper we reviewed how the creation of large international trial networks such as PRINTO and PRCSG, the definition of internationally recognized and standardized outcome measures and definitions of improvement, the validation of quality of life instruments, the adoption of adequate legislative measures (pediatric rule), have created the basic premises for the best future assessment of the PRD. This progress now offers children with PRD the same opportunities as adults to be treated with drugs whose safety and efficacy have been assessed through legitimate scientifically valid investigations.