CLEO is currently measuring the branching fractions of the exclusive decays B → π, ρ, ω, η/v with the goal of extracting |V_(ub)|. In total, 9 fb~(-1) of CLEO II and II.V data, taken at the γ(4S) resonance, will be utilized to do this. Measurement errors on these heavy to light decays are largely dominated by theoretical uncertainties in the modeling their QCD interactions. We also discuss work on a relevant analysis of CLEO III data, the decay D~0 → πlv. Because this too, is a heavy to light decay, measurements of the branching fraction for this mode will help constrain theoretical models of the difficult b → u semileptonic decays, and ultimately it will help towards a more precise measurement of |V_(ub)|.
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