Project purposes: to conduct a cross-linguistic survey of reciprocal constructions, and collect the results in a web-accessible database; to carry out in-depth studies of reciprocity in particular languages, and cross-linguistically robust analyses of particular phenomena; and to develop an integrated typology of reciprocal constructions and symmetric predicates.

The project was a collaboration of the Utrecht institute of Linguistics OTS and the Free University of Berlin.

Data was collected via questionnaire-driven interviews with native speakers, questionnaires completed by language specialists, and perusal of published reference grammars. Data was analyzed and entered in a web database. Completed descriptions of the reciprocals of 110 languages are publicly available via the project website, and can be browsed or searched for on the basis of numerous properties.