The formation of dendritic arbors is necessary for the proper establishment of neuronal circuits. The Drosophila transcription factor Spineless has been shown to play an important role in the control of dendritic morphogenesis, although the pathways through which it functions are not completely understood. Here, we show genetic evidence that Spineless interacts with the actin/microtubule cross linking protein Shortstop to control the dendrite arbor development of the dendritic arborization (da) sensory neurons. In addition, we have discovered a novel function for spineless as we show that spineless mutant larvae exhibit an increased sensitivity to specific odorants in the absence of morphological defects of the chemosensory organs. These data show that spineless acts in multiple cell-specific contexts to control the diversification of sensory neuron morphology and function.