The field of multimorbidity is often perceived as complex. Despite this, the ABC of Multimorbidity provides a comprehensive, but refreshingly comprehensible, overview of the subject. The book is novel in its content, and covers the work of a group of well-informed authors currently leading the field of research on multimorbidity. With a specific focus on primary care, the aims are to inform and educate the medical community on the prevailing issues surrounding multimorbidity.

Its primary objectives are to highlight both the nature and extent of multimorbidity and its implications for individuals, clinicians and health systems alike. In so doing, the authors have reconciled some of the disparate views that complicate the literature. In the first chapter, ‘Introducing Multimorbidity’, for example, the authors (Fortin, Mercer and Salisbury) demystify the fundamental concepts by describing the commonly observed definitions and factors associated with multimorbidity. The authors also introduce the case studies – or vignettes – which are used throughout the book, and carefully serve to capture the patient's personal narrative. The vignettes add value to the book, by supporting its central theme of a ‘holistic approach to care’. Throughout the book, the authors reinforce the idea of anticipatory, inclusive-centred care (p. 18), which encompasses not only the patient's physical condition but their emotional and social circumstances. Furthermore, the book carefully summarises the objective and subjective ways in which multimorbidity affects an individual; extending to health-care expenditure, hospitalisation, functional status and quality of life. The authors advocate for the role of primary care and generalist skills in promoting efficient, continuous, patient-centred care for individuals with multimorbidity. In support of this view, Chapters 5 (Mercer and Salisbury) and 6 (Stewart and Fortin) make useful reflections on how to provide optimum care and actualise the patient-centred approach. Later chapters also examine the changes required at policy and practice level to meet individual needs – conceptualised through the balance between a ‘patient's capacity’ and their ‘treatment burden’ (pp. 30–1). The study of the needs and requirements of patients with multimorbidity, at both the micro- and macro-level, is one of the major strengths of the book. There is also a chapter dedicated to the economic considerations of an increasingly multimorbid population. Although the graphical evidence examined in the chapter is taken from the United States of America, with multimorbid patients being viewed as consumers (p. 12), the authors balance this view by incorporating evidence from other high-income countries. The authors also do well to highlight some of the pertinent issues, such as the management of mental health alongside multimorbidity and the conflicting evidence related to quality care. The breakdown of these topics is presented in a manner that makes it easy for those interested in multimorbidity to apprehend quickly.

Overall, the book successfully delivers on its objectives, with only a few limitations. Firstly, the extent to which the recommended practices are universally acceptable is unclear; and their potential challenges are sometimes under-recognised. For example, Chapter 7 (Terry and Cejic) introduces the role of the ‘electronic medical record’ (EMR) in supporting the complex care required by multimorbid patients. The authors propose advanced EMR functions that ‘could facilitate follow-up activities by the practitioner; for example, sending a secure email to a patient’ (p. 28). Computer-based technology is deemed necessary to advance care for patients with multimorbidity. However, the authors fail to address the possible risks, such as high costs, data protection issues or the increased demand on patients who are less technologically able. Secondly, there is a lack of detail on the risk factors of multimorbidity. In Chapter 2 (Akker and Muth), the inverse relationship between socio-economic status and multimorbidity is discussed, without acknowledgement of other confounding factors, such as the consumption of alcohol and use of tobacco. Finally, the book underscores the importance of integrating specialists into the primary care system – but there is only a brief mention in Chapter 11 (Salisbury and Roland). In the United Kingdom, for example, specialists in out-of-hospital settings can help greatly to deliver the co-ordination and clinical expertise needed to improve care for those with multimorbidity.

These minor shortfalls do not undermine the book's value but are merely pointers for further iterations. Overall, the ABC of Multimorbidity will serve as an invaluable guide to inform its readership, composed of clinicians, students and researchers working in primary care. Multimorbidity is not a new phenomenon – although it has only been given its required attention within the last decade. In this respect, the book is an essential contribution to its field. As the first book of its kind, it's no doubt that its readership and impact will be wide. This book is a major achievement that draws upon the key concepts and theories surrounding the literature on multimorbidity, making it an indispensable resource for primary care practitioners.