The quenching properties of a series of oligodeoxyribosides bearing fluorophore "bases" are described. Sequences of adjacent, pi-stacked pyrenes exhibit stronger electronic interactions visible in both absorbance and emission spectra than pyrenes that are insulated by intervening adenines. Quenching by N,N'-dimethyl-4,4'-bipyridinium dichloride is efficient for excimer- and exciplex-forming oligomers, with Stern-Volmer constants comparable to conjugated polymer "superquenching" schemes.