As our simple model based on the Förster theory predicted, we were indeed able to observe enhanced energy transfer when a single donor and multiple acceptors were placed on an avidin molecule. The measured transfer efficiencies correlate very well with the modeled predictions. The size of avidin is similar to the size of a fab fragment of an antibody. The extent of the increase in transfer efficiency is encouraging, and it is possible to further increase the number of acceptors and still have a functional protein. Good agreement between the model and the experimental data for all three cases indicates that, in spite of the many assumptions made in the model, it is able to describe the ensemble behavior very well. By measuring the emission anisotropies of the donor and acceptor, we confirmed that probe mobility is high and the orientation factors of each acceptor in relation to donor averages is close to the assumed value of 2/3. Also, we were only able to determine the average labeling efficiency (i.e., average number of acceptors per avidin tetramer). However, we realize that this labeling is statistical, and that in a real system we have to deal with a distribution (typically a Lorentzian distribution) of proteins that are labeled with different numbers of acceptors. For example, in the case of a labeling efficiency of 6, the number of proteins that are labeled with six dyes will constitute more than 35% of entire population. The total number of proteins with five to seven dyes will constitute over 70% of entire population. More importantly, the number of protein molecules without a dye will be below 1%, and the number of antibodies with a single dye will be only 1.3% of the population. Therefore, almost 98% of protein molecules have two or more acceptors. The FRET efficiency depends on the number of acceptors, but our experimental results show that the lower the FRET efficiency of a fraction of molecules with a smaller number of acceptors is compensated by an equivalent fraction with a higher than average number of acceptors. It should be beneficial to use a larger labeling efficiency in order to avoid contributions from pairs without acceptor-labeled proteins. Interestingly, a labeling efficiency of 6 already shows that only 1% of the proteins are unlabeled, and we conclude that labeling efficiencies larger than 4 are experimentally acceptable. Good agreement between the calculated and measured FRET values confirms that one can use proteins labeled with many acceptors to detect intermolecular interactions at large distances. At large labeling efficiencies, even quantitative measurements of separation distances much greater than 100 Å should be possible as long as the protein size is known and the labels are randomly distributed. In practical terms, this is not a major hurdle.