The Linguasphere Observatory (or "Observatoire", based upon its original French and legal title: ) is a transnational linguistic research network. It was created in Quebec in 1983 and was subsequently established and registered in Normandy as a non-profit association under the honorary presidency of the late Léopold Sédar Senghor, a French-language poet and the first president of Senegal. Its founding director is David Dalby, former director of the International African Institute and emeritus reader in the University of London, and its first research secretary was Philippe Blanchet, a Provençal-language poet currently serving as Professor of Sociolinguistics at the University of Rennes. Since 2010, the deputy director and webmaster of the Observatoire has been Pierrick le Feuvre,with the chairman of its research council being Roland Breton, emeritus professor at the University of Paris VIII. The Observatoire's research hub is currently based in the European Union, in Carmarthenshire, Wales (UK) and in Paris. Its title in Welsh is Wylfa Ieithoedd, literally the "Observatory (of) languages", and its publishing associate (also in Wales) is the Gwasg y Byd Iaith, i.e., "Linguasphere Press" or literally "Press (of) the world (of) language".
The Observatoire has developed an innovative scheme of philological classification, coding all living and recorded languages within a global referential framework or "linguascale". This Linguascale Framework uses a decimal structure (see below) to record both genetic and geographic categories of relationship (termed phylozones and geozones, respectively).
In 1999/2000, the Observatoire published David Dalby's 2-volume Linguasphere Register of the World's Languages and Speech Communities. Reviews were published by Edward J. Vajda in Language and by Anthony P.Grant in Journal of the Royal Anthropological Society.
The Observatoire has now prepared a revised edition of the Linguasphere Register from 2010, the first of a projected series of regular updates at 10-year intervals. The current edition (LS-2010), comprising substantial materials from the foundation edition of 2000, is published online from 2011 as a freely available public resource and an online data-base, compiled and co-ordinated by David Dalby and Pierrick le Feuvre. Provision is made for the online gathering of additional and improved data, and for the open discussion of proposals and criticisms.