The luminescence of Perylene Orange and LDS821 in poly(methyl methacrylate) (PMMA) following a 532\text{\hspace{0.17em} nm} irradiation yielded information on photodegradation and energy transfer. The irradiation of the Perylene Orange∕LDS821∕PMMA films resulted in (i) a maximum in the Perylene Orange fluorescence photodegradation profile and (ii) an enhancement of the LDS821 fluorescence relative to the LDS821∕PMMA films. These results are attributed to an energy transfer from the Perylene Orange to the LDS821 with an energy transfer rate constant of \text{5.19}\pm \text{0 .75 \hspace{0.17em}}\left(\text{2}\sigma \right)\times {10}^{11}{\text{M}}^{-1}{\text{s}}^{-1} and a Förster critical radius of 65.7\text{\hspace{0.17em} Å} . Fluorescence half-quenching and time-resolved fluorescence measurements attributed energy transfer to the Förster energy transfer with minor contributions of radiative energy transfer.