Over the course of development, the central nervous system grows into a complex set of structures that ultimately controls our experiences and interactions with the world. To understand brain development, researchers must disentangle the contributions of genes, neural activity, synaptic plasticity, and intrinsic noise in guiding the growth of axons between brain regions. Here, we examine how computer simulations can shed light on neural development, making headway towards systems that self-organize into fully autonomous models of the brain. We argue that these simulations should focus on the ?open-ended? nature of development, rather than a set of deterministic outcomes.