The ultimate objective of this program is the cure of children with cancer. The program is a coordinated effort of therapy and study which includes therapeutic trials, studies of tumor cell biology, and studies of the effects of therapy on normal tissues. The program consists of a core section and four projects. The core section provides for resource personnel, patient data base, biostatistics, and two resource laboratory functions - a tissue culture and cytogenetics laboratory and an animal xenograft developmental laboratory. The projects are: (1) neuroblastoma therapy and cell biology; (2) rhabdomyosarcoma: a laboratory model for pharmacological studies; (3) Ewing's sarcoma therapy and cell kinetics as well as features of biological behavior; (4) phase I and II trials of new agents for refractory tumors. All projects have the same ultimate objective through a variety of disciplines and approaches. The organizational structure provides the means for unified and coordinated effort.