Experimental layering: paving the way for, or raising barriers to optimal policy mixes?

Experimentation is gaining traction as a policy strategy. No longer are policy instruments developed by public agencies and implemented only after lengthy internal debates and ex-ante cost benefit analyses. Currently, policy is often the outcome of a deliberative and ongoing process of problem solving by a wide range of governmental and non-governmental actors. With this experimental policy making also a whole new pallet of policy instruments has developed. Typically, these do not replace existing policies or policy mixes, but are added to it.This research paper questions how this experimental layering may be used as policy design strategy to strengthen existing policy mixes. Using earlier literature on experimental governance and a series of original case studies of experimental layering in the Australian and Dutch buildings sectors it finds that experimental layering comes with advantages and disadvantages alike. In an ideal situation experimental layering may result in valuable knowledge on what a governed sector is willing and able to change, and lessons on how this change may be achieved. Incremental layering may then pave the way for successful policy change. In a less ideal situation experimental layering may hamper successful policy change when policy makers are blinded by novelty of the experiment, captured by the governed industry, or are too eager to make the experiment work.