Life is full of decisions, and the life of a neuron is no exception to this rule. Neural progenitor cells often need a little help in choosing their fate, and considerable progress has been made in identifying the factors that guide them through the series of decisions that they face during their early lives.

Bertrand et al. (page 517) introduce us to a family of basic helix–loop–helix transcription factors that are encoded by the so-called 'proneural genes'. These regulators of gene expression are required for some of the earliest decisions that a neuronal precursor cell has to make. They are not only involved in determining which cells in the primitive ectoderm will go on to form neurons, but have also been shown to control certain aspects of the early stages of neuronal-subtype specification. Their story begins with the discovery of the achaete-scute complex and the atonal gene in Drosophila, both of which are crucial for these processes in the fly, and are now known to have homologues with similar functions in vertebrates.

Once a cell has chosen to become a neuron, it must decide what type of neuron it is going to be, and an important part of this decision is the acquisition of the neurotransmitter phenotype. Goridis and Rohrer (page 531) describe the regulatory genetic circuits that underlie neurotransmitter choice in the two classes of neurons that are best understood in this regard — those that use catecholamines or serotonin as their neurotransmitter. The authors describe how neurons from diverse origins can use variations on a core developmental programme to arrive at the same neurotransmitter phenotype, and how some of the factors that are involved also help to define other features of the neuronal phenotype.