Users of the COIL data are asked to use the following citation:

Koremenos, Barbara (2013). The Continent of International Law. Journal of Conflict Resolution, 57(4): 653-681.

Data File Description

Short description in text format of all files on this page.

Main Data File

Comma-separated text file (.csv) with the COIL data as described in the list of questions released, as well as some additional variables.

COW Country Codes

Comma-separated text file (.csv) with country names and country codes from the Correlates of War (COW) project, which can be used to match the COIL data with other data sets. The file covers all agreements in the sample. Also contains agreement name, UNTS number, COIL identifier, and year of signature.

List of Questions Released

.pdf document with a list of all questions from COIL released on this website. Sorted by broad categories.

List of Agreements, by Sub-Issue Area

.pdf document with a list of all agreements included in the current release of COIL, sorted by sub-issue areas. Also includes the signatories (if bilateral), the signature date, and the UNTS number for each agreement.

Cooperation Problems

.pdf document with definitions and examples of all cooperation problems that are coded in COIL.


.pdf document with the glossary used for the coding of the agreements. Includes extensive explanations, definitions and examples as well.

Coding Instrument

.pdf document with the instrument used for the coding of the agreements, with all questions covered by COIL.