While the role of consultants in the policy process has long been a concern for scholars of public administration, public management and political science, empirical studies of policy-related consulting are scarce, with little quantitative data. The country-level case studies in this book shed light for the first time on a number of important but as yet under-researched questions. The first is the actual extent of the use of government consulting in a number of countries, and what have been cross-time developments: to what extent has the use of consultants grown over time, and what are the (political, fiscal-economic, society, policy-related) factors that explain greater or lesser growth in a particular country or sector? The second is the question of what role(s) consultants play in the public sector and how large is the share of these consultants in policy work (policy analysis, policy advice, implementation and evaluation).

Demands made by the UK government for external policy support are big business, where the highest spend on consultants has been calculated at £2 billion in 2003–2004 (NAO 2006), and currently major consultancy firms are active in bidding for six months of Brexit work with a price tag of £1.5 million (Martin 2017). At the same time, the focus has been on review and retrenchment, with a fall in spending to £1.8b in 2005–2006 (NAO 2006), whereby ‘the government is determined to make every taxpayer penny count’ and the ‘Cabinet Office is working to help departments reduce reliance on everything from expensive consultants to print cartridges’ (Gov.uk ). Thus, it seems there is recognition of a contribution to public policy that is beyond ‘in-house’ capacity: ‘when used correctly and in the appropriate circumstances … [they] … can provide great benefit to clients – achieving things that clients do not have the capacity or capability to do themselves’ (NAO 2006: 4).

The use of external consultants by the public sector has been an increasingly relevant area of focus for almost three decades, for both government bodies (ANAO 2001; House of Commons Committee of Public Accounts (UK) 2010) and academics (Bakvis 1997; Perl and White 2002; Saint-Martin 2005; Speers 2007; Howlett, Migone and Seck 2014; Howlett and Migone 2014). This is due to both the costs and the role of private sector entities in shaping policy capacity and policy choice. Aside from the most recent contributions, the main focus has been the financial impact of contracting out this function rather than on understanding how external sources have affected the capacity of departments and other government units (Riddell 2007). There are various reasons for this trend.

As the Introduction to this book has argued, governmental use of consultancy services has long been a concern for scholars of public administration, management and political science (Howlett and Migone 2013a, 2013b; Kipping and Engwall 2003; Graeme and Bowman 2006; Guttman and Willner 1976; Rosenblum and McGillis 197).Although the impact of policy consulting is generally expected to be fairly broad, most of these studies have focused on a narrow set of questions related to the effect of contracting out on levels of public service employment and budgets (Dilulio 2016; Guttman and Willner 1976; GAO 2011) rather than on policy outcomes. Much existing research has focused either on placing this expansion in a historical perspective (McKenna 1995, 1996, 2006), or assessing its underlying causes and consequences (David 2012; Berit and Kieser 2002; McGann 2007).

The externalization and politicization of policy advice has received an increasing amount of scholarly attention in recent years (see Bakvis 1997; Macdonald 2011; Craft and Howlett 2013). Existing research focusses mainly on the visible actors, such as political advisers (Shaw and Eichbaum 2018), advisory committees (Siefken and Schulz 2013), knowledge institutions (Blum et al. 2017) and lobbyists (Fraussen and Halpin 2017). These actors are interesting because of their potential influence on the policy process in their respective roles as agenda-setters, framers, policy entrepreneurs or legitimizers. They are also important in the sense that they can strengthen or weaken the role and position of traditional political-administrative actors (such as legislators, ministers, civil servants and regulators). However, theoretically and empirically very little is known about the role and influence of the less visible type of actors: external personnel who are hired on a temporary basis as policy or management consultants (but see Howlett and Migone 2013a; Van den Berg et al.