Health systems are changing rapidly in response to new threats to population health from lifestyle diseases and long-term conditions, the global effects of climate change and the need for sustainable development also has an impact. Public health, as a set of skills to improve health and with its focus on the health of communities rather than individuals, is at the forefront of current health and health care policy and practice. In England, public health has been going through a major reorganisation, with local public health functions now returned to local authorities after nearly 40 years of being part of the National Health Service (NHS) and the creation of a new national public health agency – Public Health England – which, while being part of government, is operationally autonomous. The new organisational architecture introduced by the Health and Social Care Act 2012, and implemented in April 2013, has given rise to substantial uncertainty, and some confusion, about roles and responsibilities in the new system and what they mean for the future context of public health commissioning and governance. While the changes have been broadly welcomed, developing the new public health system places enormous challenges on those leading it and also those working within it.

This series of books on public health policy and practice endeavours to strengthen and add to the knowledge base on UK public health and address gaps in evidence and existing practice skills. The series has its roots in the publication of the Wanless Report (Wanless, 2004), the Cooksey Report (Cooksey, 2006) and a programme of research funded through the National Institute of Health Research (NIHR) Service Delivery and Organisation Programme (SDO) – now called the Health Services and Delivery Research programme. Cooksey identified the SDO Programme as filling an ‘R&D market gap’ and, therefore, of fundamental importance to the NHS (Cooksey, 2006). Following publication of the Cooksey Report, the Department of Health published Best research for best health (DH, 2006) and the government specifically highlighted the need for the SDO Programme to commission research on public health service delivery and organisation.