Kingdon's multiple streams approach has recently been applied to study implementation across sectors or levels of government. Building on these contributions, we suggest that two streams are especially important in shaping implementation: organizational problem constructions, and political pressure from the centre. These variables produce a four-way typology of implementation modes. We test the model by analysing implementation of UK targets on asylum, defence and climate change, drawing on 54 semi-structured interviews with policy actors. The analysis shows how organizations can shift between modes of implementation over time, responding to changes in organizational problems and central political commitment to the policy.

The multiple streams approach (MSA) developed by John Kingdon (1984) is enjoying something of a renaissance, with a number of recent contributions suggesting new and extended applications of the theory. While MSA was originally developed to explain agenda-setting in US public policy, many authors have suggested that it offers a useful framework for studying two additional aspects of policymaking. Firstly, MSA has been used to explain how policies developed by a central or superordinate authority are applied across sectors or levels of government (Cairney 2009; Ackrill and Kay 2011; Ackrill and Zahariadis 2013; Bache 2013; Bache and Reardon 2013). The second, often overlapping, application of MSA is to explain policy implementation following the initial stage of agenda setting (Lemieux 2002; Zahariadis 2003; Exworthy and Powell 20014; Ridde 2009; Howlett, McConnell and Perl 2014). In line with these contributions, we believe that MSA is well suited to analyse how policies are applied and implemented across space and over time. By conceiving of policies, problems and politics as largely independent streams, MSA allows one to treat policy as an exogenous variable, developed or imposed by a central or superordinate authority. How this policy is implemented then depends on its confluence with local or sectoral problem and politics streams.
However, we suggest that MSA needs further theoretical specification in order to be usefully applied to explain implementation across units or sectors. We propose drawing on theories from organizational sociology to develop a number of theoretical claims about how the convergence or divergence of streams affects implementation. This implies focusing on the organizations in the public administration responsible for the detailed elaboration and implementation of policy. We suggest that two streams are particularly influential in shaping implementation: organizational problem constructions, which need to find a match with policy emanating from the central or superordinate authority; and the political stream, especially the level of commitment of the central authority to the policy. We argue that different configurations of these two streams yield four possible implementation modes: consensual implementation, bottom-up implementation, non-implementation, and coercive implementation/decoupling.
In the second part of the paper we test and refine these claims by analysing the implementation of targets in three areas of UK policy: asylum, defence procurement and climate change. The implementation of targets under the Labour government of 1997-2010 offers an excellent case for applying our modified MSA. Through its series of Public Service Agreement targets, the Labour government attempted to roll out a single solution (performance targets) across a range of different policy areas, each of which was characterised by a distinct politics stream, and diverse organizational problems. The analysis is based on 54 semi-structured interviews conducted with government officials, special advisors and politicians involved in developing and implementing targets in the core executive and in the respective government departments.