Prader-Willi syndrome (PWS) is a rare genetic disorder characterized by neurodevelopmental signatures that includes, among others, intellectual disabilities and learning impairments, accompanied by sleep disturbances. These pathophysiological consequences can be due to deletion, uniparental dysomy (UPD), or imprinting defects of paternal expression of genes in the human 15q11-13 locus. To accelerate the research for PWS, several experimental models are under consideration. One of our team (Tucci’s lab) compared pre-clinical features of PWS both in vivo and in vitro, and recently reported common genetic abnormalities across the two experimental systems, as well as aberrant spontaneous activity and reduced synchronization in neuronal networks of cortical neurons in a PWS mouse model [1-3]. Although PWS mouse models are instrumental in dissecting PWS phenotypic mechanisms, species-specific genetic differences [4] together with the distinctive imprinting complexity of the human locus, motivate efforts in developing novel experimental models to address PWS pathophysiology and explore effective therapies [5]. Self-organized 3D cerebral organoids generated from patient-derived induced pluripotent stem cells (iPSCs) have recently been shown to broadly recapitulate cellular, transcriptional and epigenetic features of the developing human brain. These characteristics have made cerebral organoids compelling models to investigate human brain development, evolution and disease [6, 7]. Moreover, directed differentiation protocols have been developed to effectively guide the generation of region-specific brain organoids [6]. In particular, cortical organoids (cOrg) - already established in our lab - recapitulate in vitro fundamental aspects of human cerebral cortex [8], including human specific outer radial glial progenitors (i.e. oSVZ) as well as the exceptional diversity of glutamatergic projection neuron subtypes (PN) and astroglia, characteristic of the cerebral cortex [9-11] (Fig1a). In line with recent findings reporting cOrg electrical properties [12], our cOrg and display network-level neurodynamics, further supporting the possibility to investigate physiological basis of network assembly during human brain development (Fig1b). Thus, we propose here to generate 3D cOrg from PWS-patient derived iPSC as suitable model to study human specific PWS pathological phenotypes and specific neurodevelopmental features of PWS, yet not fully understood. We aim at dissecting, for the first time, alterations in gene expression at single cell resolution, molecular regulation and electrophysiological neuronal network dynamics in PWS patients-iPSCderived cOrg. Our integrated analysis at intersection of molecular and electrophysiological will shed light on molecular pathways and functional dynamics that are affected in PWS underlying the complex clinical features, while providing innovative framework for therapeutic approaches.