Developmental biology is making tremendous progress in describing the mechanisms that coordinate developmental programs and lead to the specification and differentiation of the correct cell at the correct position with appropriate synaptic or cell–cell contacts. In parallel, progress in microscale and nanoscale technologies and microfluidics is revealing new insights into single cell development in a specific environment. With these approaches it becomes possible to pinpoint the master genes that control the specification and differentiation of a single cell. In addition, these new technologies are also providing means to control microenvironments and possibly direct cell differentiation. They could also be valuable in understanding the role of a cell environment versus the genetic determinants. To revue what micro and nano-tools could offer to understand development, we will focus on the development of the nervous system.