The focus of this book is on the level of inequalities in access to health care services faced by diverse populations with a high level of need, which may be exacerbated by unprotected systems of human rights, and the inability of health care services to respond to specific needs. Different chapters present case studies of unequal access for three broad categories of vulnerable populations linked to socioeconomic status, weakly defined citizenship, and polyethnic societies (including studies on prison, asylum seekers, and Roma populations). The book takes an original approach, being the first to attempt to collect varied information to describe and/or evaluate experiences targeting these population groups. This topic is highly relevant in the current context of growing diversity and movements of populations between countries. The authors show that strategies to tackle the defined inequalities should depend on context, entail cooperation with other areas of social policy, and should consider cooperation and attitudes. The choice of a delivery model should therefore be context and group specific, and take into account possible trade offs with other objectives that policy makers may wish to achieve. Innovative and responsive programmes for the special needs of special populations are required, which however, also creates difficulties in evaluating these programmes. The volume could have been improved with a more systematic treatment of barriers to access across chapters and by making more explicit links between unequal access and current trends and issues in health care reform (that is, equity compared with cost containment or devolution). The concluding section might have been strengthened if it had adopted a similar structure to earlier parts the book, as the population groups seem to have common access issues. Reducing some sections in the book, for instance those covering historical background, might also have been beneficial. Given that most of the problems outlined in this study apply to low income countries, some reflection on this fact and the particular challenges faced in these settings would be of great value. The book is accessible for a non-technical reader and is an important contribution as an introductory text in this area.