The energy transfer processes between polyfluorene and tetraphenyl porphyrin have been investigated through steady state and time resolved measurements. Radiative transfer is found to be negligible and so the results are analyzed in terms of Forster resonance energy transfer. Rate equations are fitted to the experimental data to obtain values for the concentration dependent energy transfer rate. From this, we calculate a value of 38 Angstrom for the energy transfer distance. This compares well with the value for the Forster radius we calculate from the spectral overlap, even though Forster theory is not strictly valid for this system. (C) 2003 American Institute of Physics.