This volume has both the merits and defects that characterize most symposia publications in that the wealth of viewpoints expressed stimulates the reader, but leaves a bewildering number of unanswered questions and unresolved contradictions. The various sections are addressed, of course, to specialists and hence, will be most useful to researchers in the various fields and to advanced students. Five sessions are reported, devoted respectively to resistance to microbicides; resistance to herbicides and insecticides; tolerance and addiction to drugs and alcoholism; resistance factors, infectious agents and cancer cells; physiological, chemical and genetic viewpoints. The reports of the question and answer period held at the end of each session serve to bring out viewpoints of participants in the symposium, other than the formal speakers.

Despite the diversity of organisms concerned, certain ideas seem to be common regarding the phenomena of resistance.