The cochlea, a coiled structure located in the ventral region of the inner ear, 
acts as the primary structure for the perception of sound. Along the length of 
the cochlear spiral is the organ of Corti, a highly derived and rigorously 
patterned sensory epithelium that acts to convert auditory stimuli into neural 
impulses. The development of the organ of Corti requires a series of inductive 
events that specify unique cellular characteristics and axial identities along 
its three major axes. Here, we review recent studies of the cellular and 
molecular processes regulating several aspects of cochlear development, such as 
axial patterning, cochlear outgrowth and cellular differentiation. We highlight 
how the precise coordination of multiple signaling pathways is required for the 
successful formation of a complete organ of Corti.