Evolving evidence indicates that tumor cells can transdifferentiate between distinct transcriptionally-determined cell states with changes in resultant phenotypes, a phenomenon known as cellular plasticity. These transitions are not driven by genetic mutations and typically in contrast to normal developmental processes, may proceed bidirectionally. Here, we review the role of cellular plasticity in the aggressive childhood solid tumor, neuroblastoma. We discuss the detection of two cell states, termed mesenchymal (MES) and adrenergic (ADRN), their properties and the transcriptional circuitries that control them, their relation to the normal embryogenesis of the sympathetic nervous system and their potential role in drug resistance, escape from therapy and development of relapse.