This volume contains papers presented at the Fourth International Conference “Human Language Technologies – the Baltic Perspective” (Baltic Hlt 2010). The series of Baltic HLT conferences provides a forum for the sharing of recent advances in human language processing and for promotion of cooperation between the research communities of computer science and linguistics from the Baltic countries and the rest of the world. The conference brings together scientists, developers, providers and users to discuss state-of-the-art of Human Language Technologies (HLT) in the Baltic countries, to exchange information and to discuss problems, to find new synergies, and to promote initiatives for international cooperation.

The first larger pan-Baltic event on HLT research was the seminar “Language and Technology 2000” organized by Andrejs Spektors and the Institute of Mathematics and Computer Science, University of Latvia in Riga in 1994. In 2004, ten years after this seminar, Andrejs Vasiļjevs and Inguna Skadiņa initiated the first international Baltic HTL conference organized by the Commission of the Official Language of the Chancellery of the President of Latvia. Einar Meister took over this initiative with the second conference in 2005 in Tallinn organized by the Institute of Cybernetics and Institute of Estonian Language. Successful continuation of the series was ensured by Rūta Marcinkevičienė who initiated the third Baltic HLT conference in Kaunas in 2007 organized by Vytautas Magnus University and the Institute of Lithuanian language.

This fourth conference takes place in Riga again in October 7–8, 2010. We would like to thank the supporters and organizers of this conference: Tilde and the Institute of Mathematics and Computer Science, University of Latvia. The conference was also supported by the CLARIN, LetsMT!, and ACCURAT projects.

The last three years were very fruitful for HLT researchers and developers. A new concept – language resources as research infrastructures (RI) – was introduced throughout Europe. Baltic countries have actively contributed to the first steps to create such an RI. An overview section includes two invited papers by the creators of the Baltic linguistic infrastructure presenting an analysis of the current situation in HLT in Latvia and Lithuania, and a summary on The National Programme for Estonian HLT.

HLT research in the Baltic countries was boosted by several large-scale national and international activities, such as the projects CLARIN, ACCURAT, LetsMT! and others as described in this volume. Research results, work in progress, descriptions of demonstrations, and position papers on these and other activities form the main content of this volume. The contributions were submitted by more than 75 authors from eleven countries and reviewed by an international program committee in a blind review process. Papers selected for the conference represent a wide range of topics of research in corpus linguistics, machine translation, speech technologies, semantics, and other areas of HLT research.

We hope that this volume will serve as a useful and comprehensive repository of information and will facilitate research and development of HLT in the Baltic countries and the creation of the pan-European RI of language resources and technology.