  One of the most important requirements for a detector at the ILC is good jet
energy resolution. It is widely believed that the particle flow approach to
calorimetry is the key to achieving the goal of 0.3/sqrt(E[GeV]). This paper
describes the current performance of the PandoraPFA particle flow algorithm.
For 45 GeV jets in the Tesla TDR detector concept, the ILC jet energy
resolution goal is reached. At higher energies the jet energy resolution
becomes worse and can be described by the empirical expression: sigma_E/E ~
0.265/sqrt(E[GeV]) + 1.2x10^{-4}E[GeV].
