Second conference on   Geometric Science of Information,
      October 28-30 2015.
    Conference on  Explicit methods in Number Theory, July 6-10, 2015, Oberwolfach (Germany).
      Conference  Curve 2015, June 22-26 2015, Paris Jussieu. 
      Programm   "Amplitudes, Motives and Beyond", May 26-June 12 2015, Mainz Institute for Theoretical Physics.
    Number theory seminar Cologne, April 27 2015.
      MPI Bonn, Manin's Seminar on Algebra, Geometry and Physics, March 10 2015.
  Workshop on  "Regulators, Mahler measures, and special values of L-functions", February 16-20 2015, Montreal.
  Research stay at the MPI Bonn, January-September 2015. 
  Workshop on  "Multiple Zeta Values, Modular Forms and Elliptic Motives II", December 2014, ICMAT Madrid.
  Workshop on  "Cohomological Realizations of Motives", 7-12 December 2014, Banff International Research Station.
  Université de Fribourg (Colloquium)
   Groups in Galway (Workshop), May 2014.
  Fall semester on  "Physics and Mathematics of Scattering Amplitudes", August - December 2013, Simons Center, New York
  Autumn school on   "Multiple Zeta Values, Multiple Polylogarithms and  Quantum Field Theory", October 7-11, 2013, ICMAT Madrid  
  Clay Mathematics Institute Workshop on  "Number Theory and Physics", September 30 - October 4, 2013, Oxford
  Exploratory workshop on  "New Approaches To Multiple Zeta Values", September 30 - October 2, 2013, ICMAT Madrid  
  AIM SQuaRES Workshop on "Explicit Computations with Reduction Theories III", September 16-20, 2013, American Institute for Mathematics, Palo Alto 
  Conference on  The Mathematical Legacy of Jean-Louis Loday, September 4-6, 2013, Strasbourg
  Conference on  Explicit methods in Number Theory, July 14-20, 2013, Oberwolfach (Germany)
  LMS Symposium on  "Polylogarithms as a Bridge between Number Theory and Particle Physics", July 3-12, 2013, Durham 
  Conference on  
Recent advances in Hodge theory: Period domains, algebraic cycles, and arithmetic, June 10-20, 2013, at the UBC, Vancouver
 Workshop on  Amplitudes 2013, April 28 - May 3, 2013, at Ringberg Castle (Tegernsee)
 Special semester on  Grothendieck-Teichmüller Groups, Deformation and Operads, Jan 3- April 26 2013, at the Newton Institute in Cambridge
 Workshop on  Amplitudes and Periods, December 3-7 2012, at the IHES in Paris
 Heilbronn Workshop on  String Theory and Arithmetic Geometry, September 3-7 2012, at the Heilbronn Institute in Bristol  
  Workshop  Periods and Motives July 2-5 2012, at the ICMAT in Madrid 
  Special session of the Seminaire Mediterraneen d'Algebre et Topologie (in honour of J.-L. Cathelineau) on
 Polylogarithms in Algebra and Topology, June 14-16 2012, in Nice
  Conference on  Arakelov Geometry and K-theory, May 21-23 2012, in Toulouse
 
AIM SQuaRES Workshop on "Explicit Computations with Reduction Theories II",  American Institute for Mathematics, Palo Alto, February 2012
 Workshop "Theorie des nombres et applications", January 16-20 2012, at the CIRM in Luminy 
 Workshop on (Polylogarithmic) Webs, the so-called   Journees Textiles, November 22-25 2011, in Rennes 
   North British Mathematical Physics Seminar, October 29, 2011, in Durham
 Explicit Methods in Number Theory, Oberwolfach July 17-23, 2011
 Arbeitstagung Bonn 2011 (June 24-30), Bonn 
 Conference May 2-6 2011 in Bristol (with a  poster), organised jointly with Richard Hain, sponsored by the Heilbronn Institute, on "Multiple zeta values, modular forms, and elliptic motives"  
 
AIM SQuaRES Workshop on "Explicit Computations with Reduction Theories I",  American Institute for Mathematics, Palo Alto, February 2011
 
         Workshop on ``Numbers, Periods and Quantum Field Theory'' , 15-17 April 2010 (Durham) 
 
Special Event: Jan 8.-10., 2008,  "Hopf algebras and periods in QFT"
 
Special Event: Dec 12, 2007,  "Feynman Graphs and Periods Day"
 
Special Event: Dec 5, 2007,  "Multiple Polylogarithms and Moduli Spaces Day"
 
 
Special Semester on "Periods in Geometry, Arithmetic and Physics"