Four types of pyrene-labeled polystyrene samples (Py-PS) were prepared and the process of excimer formation between the pyrene labels was characterized by steady-state and time-resolved fluorescence to assess the effect the mode of pyrene incorporation into a polymer has on the kinetics of excimer formation. The pyrene label was incorporated into the PS backbone by either (1) reacting 1-pyrenemethoxide with a chloromethylated polystyrene backbone to yield the GrE-PS series, (2) copolymerizing styrene with 4-(1-pyrenyl)methoxymethylstyrene to yield the CoE-PS series, (3) copolymerizing styrene with N-(1-pyrenylmethyl)acrylamide to yield the CoA-PS series, or (4) polymerizing alpha,omega-dicarboxyl end-capped polystyrenes with L-lysine-1-pyrenemethylamide dihydrochloride to yield the ES-PS series. Steady-state and time-resolved fluorescence experiments demonstrated that the long and flexible linker of GrE-PS and CoE-PS enabled more efficient excimer formation than the short and rigid linker of CoA-PS, and that spacing the pyrene pendants in ES-PS led to a strong reduction in excimer formation. The fluorescence blob model (FBM) was applied to analyze quantitatively the monomer and excimer fluorescence decays of the four Py-PSs. The FBM analysis confirmed that the longer ether linker of GrE-PS and CoE-PS enabled the excited pyrene label to probe a larger volume inside the polymer coil. The level of clustering of the pyrene pendants was found to be minimal for ES-PS, as expected from its structural design. Interestingly, the pyrene pendants were twice more clustered for GrE-PS than for CoE-PS, despite both polymers having an identical chemical structure. The results for the GrE-PS and CoE-PS series suggest that reacting groups distribute themselves differently in a copolymer whether they are incorporated by a grafting onto reaction or copolymerization.