This book is an updated and revised version of the Oxford Chemistry Primer entitled Periodicity and the p-Block Elements. In addition to having updated and substantially rewritten parts of the first book, the most obvious change is that certain aspects of s-block element chemistry are now discussed explicitly and so this group of elements are therefore included in the title. The author has sought to provide an overview of some of the important trends (periodicity) found in the properties of the s- and p-block elements and the compounds that they form, and to provide the reader with some simple 'rules of thumb' whereby they might appreciate and better understand these trends.