This book is an overview of issues associated with the marriage penalty. The first section explains how the marriage penalty (and the marriage bonus) arises and why it is not possible to achieve simultaneously the goals of marriage neutrality and horizontal equity across families in a progressive tax system. The second section discusses the size of the marriage penalty, the bonus and importantly, the notion that the marriage penalty is not a precisely defined measure. The next section outlines the issues of equity, efficiency and simplicity that are part of the frame work for evaluating policy and the final section discusses various legislative proposals in light of these objectives. The book also estimates the effects of current tax policies on families of different types and sizes and analyses proposals to address the marriage penalty and the child tax credit. It contains a history of the development of tax provisions affecting the family.