The question evoked by the title of this book, Brexit: Why Britain Voted to Leave the European Union, will reverberate in the future. While the United Kingdom's 2016 referendum on membership in the European Union, or Brexit, is frequently regarded as an event, daily the British state and those who follow its fortunes are reminded that Brexit will be a lengthy process, accompanied by as many twists and turns, dramas and longueurs, as any other major event in history. All aspects of the decision to call a nonbinding referendum—the campaign, the vote, and the aftermath—will be the subject of interpretation, reinterpretation, and commentary for many years to come.

In their book, which is partly based on a preexisting research project on the UK Independence Party, or UKIP, and a coalition of their research interests, Harold Clarke, Matthew Goodwin, and Paul Whiteley attempt to answer the most fundamental question: Why did Britain vote the way it did? While offering some contextual and historical analysis, they make their book's main contribution through the analysis of polling data, taken both before and after referendum was announced and then during the campaign. As with any studies of voter attitudes and behavior, caveats about sampling methods and timing are important to note but are also set here within a conceptual scoping of the issues. The questions posed are those that the researchers consider to be important or have received support to investigate. However, some issues are simply not amenable to research being undertaken in this way, such as the longer-term approach of UK governments to effectively hide EU policy and legislation within domestic initiatives. There are also some groups that are critical to any understanding of the United Kingdom's long-term attitudes towards Europe and the influence that they have had on this ministerial practice, such as UK senior civil servants, who have never been polled on their attitudes to the European Union. The role of most of the press, both in its long-term antagonism to the European Union and its support for vote leave in the campaign, is not fully explored. Given these issues, what does this book tell us and does it meet the claim in its title?

Clarke, Goodwin, and Whiteley open the book by setting the political context for the decision to hold the referendum, a summary of the key events and political machinations from launch to vote, illustrated using contemporaneous polling data. They move on to set this information within a valence theory approach to political attitudes, both in general and reflected in individual voter behavior. It is here that the opinion polling research is used to analyze the trends in voters’ views about governments, the capability of such polls in dealing with key issues, particularly the economy, and to argue that, in this referendum, long-held and settled views had a considerable influence on voter behavior. The authors’ main conclusion here is that longer-term political views prevailed over issues raised in the campaign in influencing voters.

The core of the book is a discussion of the rise of UKIP as a party in the United Kingdom and its influence over the mainstream parties and their attitudes towards the European Union. This section of the book does much to identify the attractions of what has lately been termed “popularism” and of anti-immigration and outsider narratives, which in this case are inextricably bound together. The polling data cited here demonstrate clearly the fears of the Conservative Party about UKIP's influence and potential for capturing votes in critical seats, fears that influenced the prime minister's decision to commit to the referendum. There follows an analysis of why people voted as they did. Subsequent chapters consider the economic consequences of Brexit, including those related to immigration, and the last chapter discusses whether the referendum and the polling associated with it mark a trend in the European Union or will be a “one-off.”

In the longer term, chapters in this book are likely to be key reference sources, particularly those on the rise of UKIP and what influenced vote leave in the short run of the referendum campaign. The use of polling data is helpful in this analysis, as is the discussion about the role of political valence. There are, however, some issues that the authors do not fully address, and this is a challenge for all authors writing on Brexit while the process is underway. While Clarke, Goodwin, and Whitely discuss the long-held attitudes about the EU held by the British public, they do not consider the role of successive UK governments, the civil service, and the anti-EU press and how these might have influenced longer-term attitudes beyond those of supporters of UKIP. Nor do they discuss in any depth is the role of austerity in creating the political cradle for growing outsiderism that both fueled the rise of UKIP and allowed blame for its consequences, including National Health Service and public service funding reductions, to be attributed to the European Union by the Leave campaign. While the longer-term views of the electorate were clearly important, many of the Leave campaign claims did have a confirming resonance with those already inclined to vote this way and did influence swing voters. Another issue not discussed fully is the failure in the leadership of the Labor party to be actively engaged in a pro-Remain stance, again possibly because of their own fears about the loss of seats to UKIP supporting candidates in local and national elections. Notwithstanding these issues, this is book a major contribution to the literature of the conundrum that is Brexit.