The generation and refinement of dendrites is essential for normal brain development and function. However, the molecular mechanisms that govern dendritic morphogenesis are poorly understood. Recent studies from the Crabtree laboratory have uncovered a requirement for the neuron-specific chromatin-remodeling enzyme nBAF in dendritic growth and branching in response to neuronal activity. These findings highlight the significance of epigenetic mechanisms in activity-dependent dendritic morphogenesis, with important implications in brain development and plasticity.