We present time-resolved photoluminescence (PL) studies of novel first- and second-generation electrophosphorescent fac-tris(2-phenylpyridine) iridium(III) [Ir(ppy)₃] cored dendrimers and compare them with neat films of molecular Ir(ppy)₃. A PL quantum yield of ∼0.8 is observed in blends of the dendrimers with 4,4‘-bis(N-carbazolyl)biphenyl (CBP) at room temperature, and the natural radiative lifetime of the emissive state (1.5 μs) is observed to be the same for dendrimers and molecular Ir(ppy)₃. Quenching of the PL occurs in neat films, because of an energy transfer to less-emissive sites, which have ∼10 times lower oscillator strength. The PL quenching rate in spin-coated films of the first- and second-generation dendrimers is slower by a factor of 11 and 20, respectively, as compared to neat Ir(ppy)₃ films prepared by evaporation. Dendrimer films showed a much smoother surface than Ir(ppy)₃ films, which is consistent with more extensive aggregation of molecular Ir(ppy)₃ than dendrimers.