EPR spectroscopy was used to evaluate the dynamic motions of dendrimer end groups for a G(4)-PAMAM dendrimer. Clusters of end groups were covalently tethered together and then selectively labeled with PROXYL groups upon removal of the tether. Analysis of the EPR spectra of the spin-labeled dendrimers suggests that initial end group proximity does not appreciably alter end group presentation on heterogeneously functionalized PAMAM dendrimers after tethers are released.