the Marettimo town

Workshop on Controlled Natural Language (CNL 2009)

8–10 June 2009
Marettimo Island, Italy

Controlled Natural Languages (from Wikipedia):

Controlled natural languages (CNLs) are subsets of natural languages, obtained by restricting the grammar and vocabulary in order to reduce or eliminate ambiguity and complexity. Traditionally, controlled languages fall into two major types: those that improve readability for human readers, and those that enable reliable automatic semantic analysis of the language. [...] The second type of languages has a formal logical basis, i.e. they have a formal syntax and semantics, and can be mapped to an existing formal language, such as first-order logic. Thus, those languages can be used as knowledge representation languages, and writing of those languages is supported by fully automatic consistency and redundancy checks, query answering, etc.

Various controlled natural languages of the second type have been developed by a number of organisations, and have been used in many different application domains, most recently within the semantic web.

This workshop was dedicated to discussing the similarities and differences of existing controlled natural languages of the second type, possible improvements to these languages, relations to other knowledge representation languages, tool support, existing and future applications, and further topics of interest.

The workshop was informal with lots of time for presentations and discussions in the fashion of the seminars organised at Dagstuhl in Germany. To ensure the informal atmosphere the number of participants was limited.


The workshop took place on the Italian island Marettimo at the Marettimo Residence.


CNL 2009 addressed the following aspects of controlled natural languages (CNLs):

Accepted Extended Abstracts

Researchers submitted 31 extended abstracts of which the programme committee accepted 24. Two papers were withdrawn by their authors after acceptance. Revised versions of the remaining 22 extended abstracts were published as CEUR Workshop Proceedings (Volume 448).


Here is the detailed programme of the workshop.


Some participants presented posters of their work:


Some pictures of the event are available:

Submission of Full Papers

During the workshop authors had ample time to present their work and to have it discussed by the participants. All authors of accepted extended abstracts were then invited to submit a full paper. Subsequently, 17 full papers were submitted of which the programme committee accepted 16.

In 2010, revised versions of the accepted full papers were published as volume 5972 of Springer's LNCS/LNAI series.

Program Committee


Norbert E. Fuchs (University of Zurich, Switzerland),