Some 20 years ago, I was privileged to share in writing a book on the descriptive chemistry of the 4d, 5d, 4f and 5f metals that included these eight elements within its compass (S.A. Cotton and F.A. Hart, The Heavy Transition Elements, Macmillan, 1975). This volume shares the same aim of covering the descriptive chemistry of silver, gold and the six platinum metals in some detail at a level suitable for advanced undergraduate and postgraduate study. It does not attempt to be a comprehensive treatise on the chemistry of these metals. It attempts to fill a slot between the general text and the in-depth review or monograph. The organometallic chemistry is confined to a-bonded compounds in normal oxidation states; compounds with IT-bonding ligands are generally excluded. Their inclusion would have increased the length of the book considerably and, moreover, their recent chemistry has been extensively and expertly reviewed in the new Comprehensive Organometallic Chemistry, II, eds G. Wilkinson, F.G.A. Stone and E.W. Abel, Pergamon, Oxford, 1995.