Economic growth is neither a necessary nor a sufficient condition for environmental degradation, as the IPAT identity makes clear. However, growth can, and often will, increase degradation pressures, particularly when growth is strongly associated with greater material/resource throughput. For more information on the possible linkages between growth and the environment, see the references on the EKC hypothesis listed in the further reading section, particularly the special issue of the journal Environment and Development Economics in October 1997 (volume 2, part 4), and also of the journal Ecological Economics in May 1998 (volume 25, No. 2).