  I will review the latest results for the presence of diffuse light in the
nearby universe and at intermediate redshift, and then discuss the latest
results from hydrodynamical cosmological simulations of cluster formation on
the expected properties of diffuse light in clusters. I shall present how
intracluster planetary nebulae (ICPNe) can be used as excellent tracers of the
diffuse stellar population in nearby clusters, and how their number density
profile and radial velocity distribution can provide an observational test for
models of cluster formation. The preliminary comparison of available ICPN
samples with predictions from cosmological simulations support late infall as
the most likely mechanism for the origin of diffuse stellar light in clusters.
