Fundamental to our interaction with the world, hearing and balance require 'hair cells' in the inner ear to transduce sound, gravity or head movements into electrical impulses relayed to the brain. Our research aims to unravel the developmental mechanisms that give hair cells their characteristic shape to enable perception. Sensory ability arises through a morphogenetic process whereby intricate cytoskeleton polarization produces and orients the stereocilia bundle, the cell compartment where transduction occurs. How multiple levels of polarity are implemented and interconnected during hair cell differentiation remains largely unknown. Understanding morphogenesis in molecular detail will aid the comprehension and potential treatment of hereditary hearing loss.