Neural circuit formation shows a puzzling diversity: Some circuits are strikingly stereotypical and hardwired, whereas other circuits are highly variable, either due to substantial developmental noise or activity-dependent plasticity and learning. This has somewhat divided the field, where theories of plasticity and learning often do not consider the role of innate behavior and developmental priors, and developmental models have often ignored how learning and plasticity may help to achieve phenotypic robustness, while also enabling adaptation to changing environments. This interdisciplinary workshop will bring together experts in neural circuit evolution, function, development, and learning to explore the complex relationship between genetically-encoded hardwiring, developmental noise and plasticity. The event aims to address questions about when learning is necessary, which circuit functions can be hardwired throughout evolution, and how learning and development interact.