The papers collected in this volume were presented at an International Conference that, with the same heading, was held at the Verona University, Italy, in June 1986. The meeting was organized by the Institute of Forensic Hedicine and the Laboratory of Medical Research of the University in cooperation with the Italian Group for Mass Spectrometry in Biochemistry and Medicine. The aim of the symposium was bringing together people, work ing in different branches of the wide field of modern analytical sciences, for promoting inter-disciplinary discussions and exchange of experiences. Actually it was felt that most of the analytical problems that very often have to be faced in quite different fields (chem istry, pharmacology, medicine, biology) have similar solutions, that could be made much easier by closer contac'cs among researches of these disciplines. Original papers and invited rewiews presented during the 3 days of the conference by leading experts gave an up-to-date outline of the modern analytical methods applied in pharmaceuti cal, biomedical and forensic sciences and a glimpse of the future perspectives.