Background: To date, no data on the adherence to specific guidelines for children with chronic myeloid leukemia (CML) in chronic phase (CP) have been reported. Methods: Since 2001, guidelines for treatment with imatinib mesylate (IM) and monitoring in patients younger than 18 years with CP-CML have been shared with 9 pediatric referral centers (P centers) and 4 reference centers for adults and children/adolescents (AP centers) in Italy. In this study, the adherence to these guidelines was analyzed. Results: Thirty-four patients with a median age of 11.4 years and 23 patients with a median age of 11.0 years were managed at 9 P and at 4 AP centers, respectively. Evaluations of bone marrow (BM) and/or peripheral blood (PB) were available for more than 90% of evaluable patients. Cytogenetics and molecular monitoring of PB were more consistently performed in AP centers, whereas molecular analysis of BM was carried out more frequently in P centers. Before 2009, some patients who responded to IM underwent a transplantation, contrary to the guidelines’ recommendations. Conclusions: Our experience shows that having specific guidelines is an important tool for an optimal management of childhood CP-CML, together with exchange of knowledge and proactive discussions within the network.