An important part of materials science is the study of the behavior of materials under difficult environmental conditions. Some operating conditions have been traditional objects of study—for example, high temperatures and corrosive atmospheres. The study of materials in radiation environments gained particular significance after the advent of nuclear reactors, and radiation has joined the list of insults to which materials are subjected. Technological applications that involve significant levels of radiation include but are not limited to fission reactors, proposed fusion reactors, nuclear waste, ion accelerators, and spacecraft, with types of radiation encompassing thermal and fast neutrons, light and heavy ions, and energetic photons. More detailed information on applications and accompanying radiation fields appears in the articles published in this issue of MRS Bulletin and in the references listed under Further Reading.

The four theme articles in this issue focus on radiation effects in four families of materials commonly used in radiation environments: metals, ceramics, graphite and carbon-based materials, and polymers.