Bilateral Labor Agreements Dataset

Data visualization of global BLAs
Total number of BLAs signed from 1945 to 2015 based data from the Bilateral Labor Agreements Dataset.


Pairs of Countries have signed hundreds of Bilateral Labor Agreements (BLAs) to regulate the flow of migrants between countries. Unlike Bilateral Investment Treaties or Preferential Trade Agreements, however, BLAs have received little attention from social scientists or legal scholars. We believe this is in large part because information on the existence of these agreements has been hard to come by. To address this problem, we have engaged in a multi-year project to try and identify every BLA that has been signed from 1945 to 2015.

To identify BLAs, we took five steps. First, we searched the United Nations Treaty Series for BLAs using key words and then reviewed the results to identify relevant agreements. The specific keywords we searched for were: “labor”, “labour”, “working holiday”, “employment”, “employee”, “workers”, “frontier”, “cross-border”, “trainees”, “vocational”, and “mobility”. Second, we used the same process to search the World Treaty Index. Third, we searched the website of the International Labour Organization. Fourth, we searched the internet for BLAs that we saw mentioned in academic articles and the press during our research that could not be located in the above databases. Finally, we searched the foreign ministry databases of countries that prior research suggested had signed a large number of BLAs.

We identified 582 Bilateral Labor Agreements through this process. However, this list is almost certainly underinclusive. Many BLAs are not deposited in the major international treaty databases and they often do not receive much, if any, publicity. As a result, we know that our dataset is incomplete. We are unaware of any other public dataset of these agreements, and we believe that this is the largest list of the agreements ever compiled. We would appreciate being notified about any additional Bilateral Labor Agreements or any errors in our data.

We have created two datasets based on the 582 BLAs that we identified. The first dataset—the BLA Treaties Dataset—used the treaty as the unit of observation. The second dataset—BLAs DyadYear Dataset—uses the dyad-year as the unit of observation. The Dyad-Year dataset is structured to be ready for analysis by other scholars and includes a number of variables from other public datasets (complete citation information is in the relevant codebooks). More detail on these two agreements is below.

BLA Treaties Dataset

For this dataset, the unit of observation is a treaty. Treaties were obtained from a variety of sources, specified in the variable agreementsource. We have been able to obtain copies for 254 out of the 582 Bilateral Labor Agreements we have identified. We also categorized the agreements into three types: new, amending, and superseding. An amending agreement is one which specifically references a previous agreement and includes some changes to the terms and conditions. A superseding agreement is one which explicitly replaces a previously existing one. Otherwise, we assume the agreement to be new.

BLA Dyad-Year Dataset

For this dataset, the unit of observation is a dyad-year. The initial country-year template is based on a dataset created by the Correlates of WAR (“COW”) project, available at (we used the 2011 release). We then expanded it by adding Hong Kong, as well as the years 2012-2015 for all countries that existed as of 2011. We then populated the template with a variety of dyadic and country-level controls, e.g., migration and trade flows, GDP, and population. The complete list of controls and their primary sources are in the codebook. We merged this dataset with our list of treaties and created a number of variables corresponding to those treaties.


This research was completed as part of the University of Chicago Law School’s Policy Initiative Program. More information on the Chicago Policy Initiative Program is available here. We thank the Kanter Family Foundation for its generous support of the Policy Initiative Program and of this research project.

This project was also supported by the Coase-Sandor Center for Law and Economics at the University of Chicago Law School. More information on the Coase-Sandor center is available here.

We would also like to thank Kathrine Gutierrez, Vera Shikhelman, and Rafeh Qureshi for research assistance on this project.

Citation Information

We ask all researchers using these datasets to cite the following paper (available here):

Adam Chilton and Eric Posner. 2018. Why Countries Sign Bilateral Labor Agreements. Journal of Legal Studies 47(S1): 45-88.

Contact Information

If you have any questions, comments, or corrections, please email us at:  Adam Chilton (; Eric Posner (; and Bartek Woda (


The Bilateral Labor Agreements Dataset is available at the dataverse. Click here to download it now.