Seven diabetic children (age: 8-12 y.) participated in a study comparing CSII and conventional treatment (CT) under the same monitoring and supervision for a year. The aim of the study was to explore the feasibility, the risks and the results on the glycemic control of CSII. Mean HbAlC fell from 9.3 +/- 2.1% to 7.3 +/- 1.4% (p less than 0.001) after the first month of CSII, remaining stable thereafter and with marginally lower, daily insulin requirements. There was a trend for HbAlc to increase, (HbAlC = 8.6 +/- 1.8%) under conventional treatment. The individual means of premeal capillary blood glucose concentrations were lower under CSII than under CT, but exhibited large variability under both treatments. Symptomatic hypoglycemia was as frequent under CSII as under CT. Ketonuria occurred frequently after the night basal infusion, but was of moderate clinical relevance and mainly due to technical problems. All seven children completed the trial; 4 of them chose to return to pump treatment. No psychologically adverse effects were noted. They all liked the flexibility of lifestyle afforded by CSII, and were generally compliant with the guidelines of this regimen. The pump itself was a valuable educational tool for the children and their families. However, CSII was recognized as individually demanding. This study demonstrates the feasibility of CSII in prepubertal children, and its impact on the glycemic control. The risks of this form of intensified treatment were limited by the strict monitoring and medical supervision provided by a specialized team.