This is a post-print version of the following article: Title: The uncertain potential of policy-learning: a comparative assessment of three varieties Author: Katrin Toens & Claudia Landwehr Journal information: Policy Studies, Vol. 30, No. 3 (June 2009) DOI: 10.1080/01442870902863927 This article may not exactly replicate the final version published in Policy Studies. It is not the version of record and is therefore not suitable for citation. Provided for non-commercial research and education use. Not for reproduction, distribution or commercial use. Other uses, including reproduction and distribution, or selling or licensing copies, or posting to personal, institutional or third party websites are prohibited.