Neuronal development is often regulated by non-neuronal, `accessory' cells, but the mechanisms underlying such regulation are poorly understood. Now, Paul Whitington and colleagues report that Netrin-A (a secreted axon guidance protein) controls the dendrite orientation and migration of a Drosophila sensory neuron by directing the morphogenesis of an accessory cell (see p. 2227). Insect chordotonal organs are mechanosensory organs that contain two or more accessory cells and one neuron. The researchers report that the cap cell of v'ch1, an abdominal chordotonal organ, extends a long process soon after birth that attaches to the epidermis in the body wall. Netrin-A produced in epidermal cells at the future attachment site of this accessory cell regulates cap cell morphogenesis, they report, which subsequently aligns the dendrite of the chordotonal neuron and tows its cell body into its final position. Together, these results begin to reveal how the cap cell, which helps to transduce sensory stimuli into electrical activity in the mature chordotonal organ, also regulates the development of the organ's neuron.