In metazoan development, epigenetic mechanisms are required for the transition from multipotency to lineage commitment. Epigenetic regulation contributes to the extraordinary reproducibility and stability of multiple lineage decisions during gastrulation and organogenesis. Recent evidence indicates that phase transitions in the nucleus are involved in epigenetic mechanisms including the regulation of gene expression and therefore, potentially, lineage decisions. The perception of nuclear proteins as structured folds with extra disordered regions that can be ignored has fundamentally shifted. Intrinsically disordered regions (IDRs), often together with nucleic acids, are now thought to assemble into condensates in the nucleus. Several nuclear condensates have been documented, including the nucleolus, and recently, heterochromatin. Evidence that condensates are involved in the regulation of gene expression is also emerging. This EMBO Workshop is based on the anticipation that condensates in the nucleus will be involved in the regulation of gene expression through epigenetic mechanisms. Conversely, epigenetic mechanisms likely include phase transitions to regulate gene expression. This EMBO Wworkshop aims to juxtapose the frontier of condensates and phase transitions with chromatin and the epigenetics of early developmental transcriptional decisions in higher metazoans. We aim to catalyze interdisciplinary discussion and speculations at the forefront of an emerging interface.