The aim of this study is to compare probiotic therapy with VSL#3 versus placebo in maintenance therapy of children with mild to moderate CD, treated with either 5-ASA, corticosteroids (local or budesonide), imuran/6MP, as long as no change in medication dosage has been made in the previous 12 weeks (for imuran/6MP) or 4 weeks (for corticosteroids). The primary goal will be to compare their ability to maintain remission and to decrease disease activity in each of the two study groups. Data will be collected during this 16 week period regarding the safety and tolerability of VSL#3, as well as data of changes in stool composition of microflora upon treatment.