The main theme of this book concems the relationship, if any, between and addietion. Are they linked biochemieally? Is there a schizophrenia common factor for all addietions? We need to know whether the chemis­ try of addiction can help clarify the biochemistry of schizophrenia and vice versa. There is much anecdotal evidence that many sufferers from schizophrenia are addieted to smoking, are adversely affected by even small amounts of alcohol and do have their schizophrenie illness wor­ sened by street drugs. We would urge our readers to try to find correla­ tions between some of the findings described here on the biology of schizophrenia and what they read in the up-to-date chapters on addie­ tions. We would like to thank all the authors for the excellence of their work and for their cooperation and understanding of our needs and also, for the second time this year, to thank MTP Press for their willingness to pub­ lish a perhaps somewhat provocative book. We thank them for their humanity.