- Deputy Principal Investigator, Millenium Nucleus Center for Semantic Web Research (Funded by Iniciativa Cientifica Milenio, Chile).
- Principal Investigator, FONDECYT Project "Semantic Optimization in Tractable Classes of Conjunctive Queries" (Funded by CONICYT, Chile).
- "Semantic Acyclicity for Conjunctive Queries: Approximations and Constraints". Invited keynote speaker, 23rd Workshop on Logic, Language, Information and Computation (WoLLIC 2016).
- "Query Languages for Graph Databases: Bridging the Gap Between Theory and Practice". Invited keynote speaker, 30th Brazilian Symposium on Databases (SBBD 2015).
- "Querying Graph Databases". Invited tutorial, 32nd ACM Symposium on Principles of Database Systems (PODS 2013).
- PC Chair of the 22nd International Conference on Database Theory, ICDT 2019.
- 21st International Conference on Database Theory, ICDT 2018, Vienna, Austria.
- 44th International Colloquium on Automata, Languages, and Programming, ICALP 2017, Warsaw, Poland.
- 25th International Joint Conference on Artificial Intelligence, IJCAI 2016, July 9-15, 2016, New York City, USA.
- 19th International Conference on Database Theory, ICDT 2016, March 15-18, 2016, Bordeaux, France.
- 30th ACM/IEEE Symposium on Logic in Computer Science, LICS 2015, July 6-10, Kyoto, Japan.
- SIGMOD/PODS PhD Symposium 2015, May 31, Melbourne, Australia. (Program co-chair)
- SIGMOD Conference 2015, June 2-4, Melbourne, Australia.
- 33rd ACM Symposium on Principles of Database Systems, PODS 2014, June 23-25, Salt Lake City, USA.
- SIGMOD/PODS PhD Symposium 2014, June 22, Salt Lake City, USA. (Program co-chair)
- 30th International Symposium on Theoretical Aspects of Computer Science, STACS 2013, February 27 - March 2, Kiel, Germany.
- XXXI Conferencia Internacional de la Sociedad Chilena de Ciencias de la Computación, SCCC 2012, November 12-16, Valparaiso, Chile. (Program co-chair)
- The 2nd Workshop on the resurgence of Datalog in academia and industry, DATALOG2.0 2012, September 11-13, Vienna, Austria. (Program co-chair)
- SIGMOD Conference 2012, May 20-25, Scottsdale, USA.
- The 14th Asia-Pacific Web Coference, APWeb 2012, April 11-13, Kunming, China.
- 20th ACM Conference on Information and Knowledge Management, CIKM 2011, October 24-28, Glasgow, Scotland.
- 5th Alberto Mendelzon Workshop on Foundations of Data Management, AMW 2011, May 9-12, Santiago, Chile. (Program co-chair)
- The 13th Asia-Pacific Web Coference, APWeb 2011, April 18-20, Beijing, China.
- 31st Conferencia Latinoamericana de Informatica, CLEI 2010, October 18-22, Asuncion, Paraguay.
- 4th International Workshop on Semantics in Data and Knowledge Bases, SDKB 2010, July 5, Bordeaux, France.
- 4th Alberto Mendelzon Workshop on Foundations of Data Management, AMW 2010, May 17-20, Buenos Aires, Argentina.
- 10th International Workshop on Logic and Computational Complexity, LCC 2009, August 10, Los Angeles, USA.
- 12th International Symposium on Database Programming Languages, DBPL 2009, August 23-24, Lyon, France.
- International Workshop on Logic in Databases, LID 2009, October 29-30, Copenhagen, Denmark.
- 28th ACM Symposium on Principles of Database Systems, PODS 2009, June 29 to July 2, Providence, Rhode Island, USA.
- 3rd Alberto Mendelzon Workshop (AMW 2009): Chair of the Graduate Students Workshop, May 12-15, Arequipa, Peru.
- 12th Internacional Conference on Database Theory, ICDT 2009, March 23-25, St. Petersburg, Russia.
- 9th ACM Internacional Workshop on Web Information and Data Management, WIDM 2007, November 9, Lisboa, Portugal.
- 11th Internacional Symposium on Database Programming Languages, DBPL 2007, September 23-24, Vienna, Austria.
- 5th Internacional XML Database Symposium, XSym 2007, September 23-24, Vienna, Austria.
- Member Editorial Board Logical Methods in Computer Science.
- Editor of the Database Principles Column of the SIGMOD Record (until September 2014).
- Editor Special Issue on Foundations of Data Management Journal of Computer and System Sciences (JCSS).
- 9th Alberto Mendelzon Workshop on Foundations of Data Management (AMW 2015), Lima, Peru, May 5-8, 2015 (General Chair).
- 21st Workshop on Logic, Language, Information and Computation (WOLLIC 2014), Valparaiso, Chile, September 1-4, 2014 (Local Organizer).
- 3rd Alberto Mendelzon Workshop on Foundations of Data Management (AMW 2009), Arequipa, Peru, May 12-15, 2009 (General Chair).