Excitation energy transfer (EET) in host-guest complexes of dansylated POPAM dendrimers and xanthene dyes have been studied by transient absorption spectroscopy. EET from dansyl periphery to guests: rose bengal, eosin, or fluorescein, showed non-exponential behaviour as a result of distribution of donor-acceptor distances. Time constants range from 100 fs to 8 ps, independent of the dye and the dendrimer generation. Experiments suggested that in dendrimers binding more than one guest, EET among the guests becomes effective. Guest-host and guest-guest interactions induce non-radiative relaxation channels making excitation decays of the guests clearly faster in complexes than in solution. (C) 2011 Elsevier B.V. All rights reserved.