Superheavy elements – chemical elements which are much heavier than those which we know of from our daily life – are a persistent dream in human minds and the kernel of science fiction literature for about a century. This book is the first to treat the chemistry of superheavy elements, including important related nuclear aspects, as a self contained topic. It is written for those – students and novices -- who begin to work and those who are working in this fascinating and challenging field of the heaviest and superheavy elements, for their lecturers, their advisers and for the practicing scientists in the field – chemists and physicists - as the most complete source of reference about our today's knowledge of the chemistry of transactinides and superheavy elements. However, besides a number of very detailed discussions for the experts this book shall also provide interesting and easy to read material for teachers who are interested in this subject, for those chemists and physicists who are not experts in the field and for our interested fellow scientists in adjacent fields. Special emphasis is laid on an extensive coverage of the original literature in the reference part of each of the eight chapters to facilitate further and deeper studies of specific aspects. The index for each chapter should provide help to easily find a desired topic and to use this book as a convenient source to get fast access to a desired topic.