This chapter outlines a programme of research that examined olfactory neuroepithelium in schizophrenia as an example of the heuristic value of this research. The neurodevelopmental hypothesis of schizophrenia proposes that genetic and epigenetic factors alter early brain development, leaving the affected individual at increased risk of developing schizophrenia. The favoured model for neurodevelopment is the adult olfactory epithelium, which provides access to developing neural tissue in living patients. The olfactory neuroepithelium is capable of regeneration and there is a continual renewal of the sensory neuron. Properties of olfactory neuroepithelium cultures of individuals with psychotic disorders may have heuristic value with respect to unravelling functions related to both early brain development and even with respect to current brain function, given the continuing neurogenesis now known to occur in adult brain. In schizophrenia, olfactory epithelium has also been exploited to reveal evidence in support of neurodevelopmental aetiology for this disorder.