The developing retina generates spontaneous waves of activity that propagate up to primary visual cortex and guide the synaptic refinement of early visual circuits. Across several species, retinal waves mature in three stereotypic stages (I – III), in which different circuit mechanisms give rise to activity patterns with unique spatiotemporal properties. In the final stage (III), glutamate release from bipolar cells drives retinal waves that sequentially recruit neighboring retinal ganglion cells with opposite light responses (ON and OFF RGCs). I will discuss recent insights from our group into the circuit mechanisms of stage III waves. Using systematic combinations of dual patch clamp recordings we reconstructed the sequence of neuronal activation during stage III waves, identified intersecting lateral excitatory and vertical inhibitory networks that propagate and pattern this activity, and characterize the mechanisms of communication among neurons in these circuits. In addition, I will describe our findings on the influence of glutamatergic activity on the synaptic development of bipolar cells, highlighting novel cell-type-dependent and retrograde plasticity mechanisms.