1. Science Classifications Current situation 1)Each research group/data provider/government agency has its own classification; 2)Different data sources (funding, publications, PhD programs) use different classifications; 3)For bibliometric data, journal-level classifications, which have been the norm for decades, are not as precise as paper-level classifications (such as PubMed’s MeSH and other classifications recently developped); 4)Classifications standards shows the consensus in the community and allows for various statistics to be comparable and reproducable. 1)However, paper-level classifications are potentialy tougher to share than journal-level classifications.

2. Many sources for many purposes -Bibliographic databases -Thomson Reuters -Scopus -Governmental agencies -NSF – The Patent Board -OECD -IES: Classification of Instructional Programs -Firms / research groups -Science-Metrix -CWTS -CNS-IU -SciTech Strategies

3. Vincent Larivière is the Canada Research Chair on the transformations of scholarly communication, Assistant Professor of Information Science at the Université de Montréal, regular member of the Centre interuniversitaire de recherche sur la science et la technologie and associate researcher at the Observatoire des sciences et des technologies. He can be reached at: vincent.lariviere@umontreal.ca Websites: http://lariviere.ebsi.umontreal.ca http://www.ost.uqam.ca http://www.cirst.uqam.ca