This book considers how courts and regulatory agencies in Australia and in the US can and should assess mergers of firms which produce products or services differentiated in the minds of consumers from other products or services. (Most if not all products and services are differentiated at least to some degree so the topic is relevant to most mergers.) This book seeks the best solution for Australia to the difficulties posed by such mergers. It does so by comparing the approach taken in Australia with that taken in the US. In the US, the main method of merger analysis where there are differentiated products is to consider whether the merger of two firms will create unilateral effects i.e., higher prices, by eliminating the constraint each firm places on the other. In Australia, Courts and the Tribunal, and until recently the Australian Competition and Consumer Commission (ACCC), have not emphasized unilateral effects. Comparatively little use has been made in Australia of...