On May 14 and 15, 2009, TILEC hosted the yearly gathering of the Competition Law and Economics European Network (CLEEN). This network, which was created in 2007, associates research centers with a profile similar to TILEC·s one in order to foster exchanges of ideas, experiences and researchers. Previous meetings had taken place in Bonn and Norwich. This time, 35 researchers from the Amsterdam Center for Law and Economics (ACLE) at the University of Amsterdam, the Center for Competition Policy (CCP) at the University of East Anglia, the Robert Schuman Centre for Advanced Studies (RSCAS) at the European University Institute in Florence, the Max-Planck Institute for Research on Collective goods in Bonn, and TILEC came to Tilburg to present and discuss about 25 papers on competition or regulation issues. The keynote speeches were delivered by J. Gregory Sidak (Criterion Economics) and Edward Droste (CRA), who presented their views on the present and future of merger guidelines in the US and in Europe. The meeting, organized by Cedric Argenton and Rochelle van Rooij at TILEC, was well-received and participants look forward to the collaboration opportunities that may ensue.