The European Workshop on Economic Theory (EWET) is an annual workshop on economic theory and mathematical economics.
Established in 1991 as the European Workshop on General Equilibrium Theory, the workshop series has grown to cover, beside general equilibrium theory, research in decision theory, information economics, game theory, bargaining and matching, and social choice. 

The workshop has been hosted by the University of Geneva (1991), European University Institute (1992), Université Catholique de Louvain-la-Neuve (1993, 1997), University of Copenhagen (1994, 1999), Universitat Autònoma de Barcelona (1995, 1998), Université Paris 1 Panthéon-Sorbonne  (2000, 2014, 2018), University of Maastricht (2001), National Technical University of Athens (2002), Bielefeld University (2003), University of Venice (2004), University of Zurich (2005), Universidade Nova de Lisboa (2006), University of Warwick (co-organized with Queen Mary University, 2007), University of Salerno (2008), Universitat Pompeu Fabra (2009), Cracow University of Economics (2010), Universidade de Vigo (2011), University of Exeter (2012), University of Vienna (2013), University of Naples Federico II (2015), University of Glasgow (2016), University of Salamanca (2017), University Paris 1 Pantheon-Sorbonne and Paris School of Economics (2018), Humboldt University (2019), Western Galilee College (2021), SGH Warsaw School of Economics (2022).  

 Since 2003, the workshop includes an invited plenary lecture in honor of Gerard Debreu, presented by a distinguished scholar in fields related to general equilibrium theory. Previous Debreu Lectures were given by: Leonid Hurwicz (2003), Werner Hildenbrand (2004), Graciela Chichilnisky (2005), David Cass (2006), Andreu Mas-Colell (2007), Roger Guesnerie (2008), Roy Radner (2009), David Schmeidler (2010), Herakles Polemarchakis (2011), Yves Balasko (2012), M. Ali Khan (2013), Edward C. Prescott (2014), Nicholas Yannelis (2015), Michael Magill and Martine Quinzii (2016), Bill Zame (2017), John Geanakoplos (2018), Chris Shannon (2019), Robert Aumann (2021).

Since 2007, the workshop also includes an invited plenary lecture on topics in economic theory. These Economic Theory Lectures have so far been given by Jean-François Mertens (2007), Michele Boldrin (2008), Egbert Dierker (2009), Edward C. Prescott (2010), Nicholas Yannelis (2011), Felix Kubler (2012), Egbert Dierker (2013), Aloisio Araujo (2014), Bernard Cornet (2015), Yves Sprumont (2016), Salvador Barberà (2017), Myrna Wooders (2018), Konrad Podczeck (2019), Jean-Jacques Herings (2021), and Jan Werner (2022).