QoG Data

The ATOP State-Year dataset

Data source: Alliance Treaty Obligations and Provisions Project (ATOP)

The 5.1 version of the Alliance Treaty Obligations and Provisions (ATOP) project provides data regarding the content of military alliance agreements signed by all countries of the world between 1815 and 2018.

The authors hope the project will be useful in understanding (1) the conditions under which leaders sign formal alliance agreements and why they do so; (2) why leaders design alliances with varying obligations and provisions; (3) the effects of alliances on subsequent behavior and the role of design features in influencing these effects; and (4) the success of alliances in eliciting compliance, and the role of design features in influencing this success.

Dataset type

Time-Series

Dataset level

Country

Last updated by source

2022-08-09

Citation

When using this dataset, please cite as:

• Leeds, B., Ashley, J., Ritter, S. M., McLaughlin, M., & Long, A. G. (2002). Alliance treaty obligations and provisions, 1815–1944. International Interactions, 28, 237–260.

@article{atop1,
 abstract = {This article introduces the Alliance Treaty Obligations and Provisions (ATOP) dataset. We begin by describing the rationale for collecting the ATOP data, its scope, and some general coding rules for the project. Then we offer some descriptive statistics for phase one of the dataset, which covers the years 1815-1944, and reveal some interesting trends in alliance politics. Finally, we replicate a study of alliance formation originally conducted by Lai and Reiter (2000) to demonstrate the effect the use of ATOP data may have on past inferences about alliance politics.},
 author = {Leeds, Brett Ashley and Ritter, Jeffrey M. and Mitchell, Sara McLaughlin and Long, Andrew G.},
 doi = {https://doi.org/10.1080/03050620213653},
 journal = {International Interactions},
 keywords = {Alliance, Treaty, Obligations, International Relations, International Security, International Cooperation},
 last_updated = {2025-09-26},
 pages = {237--260},
 title = {Alliance Treaty Obligations and Provisions, 1815--1944},
 volume = {28},
 year = {2002}
}

Variables in this dataset

Browse variables and select them for download.

Member of an Alliance

QoG code: atop_ally

Member of an Alliance 0. Not a member of an alliance 1. Member of an alliance An alliance defined as a formal agreement among independent states to cooperate militarily in the face of potent ...

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Consultancy Obligation

QoG code: atop_consult

Consultancy Obligation 0. Has no Consultancy obligations 1. Has Consultancy obligations Coded 1 if the alliance member promises to consult with one or more alliance partners in the event of ...

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Defensive Obligation

QoG code: atop_defensive

Defensive Obligation 0. Has no defensive obligations 1. Has defensive obligations Coded 1 if the alliance member promises to provide active military support in the event of attack on the sov ...

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Neutrality Obligation

QoG code: atop_neutrality

Neutrality Obligation 0. Has no Neutrality obligations 1. Has Neutrality obligations Coded 1 if the alliance member promises not to join a conflict between one or more alliance partners and ...

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Non-Aggression Obligation

QoG code: atop_nonagg

Non-Agression Obligation 0. Has no Non-Agression obligations 1. Has Non-Agression obligations Coded 1 if the alliance member promises not to use force against one or more alliance partners t ...

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Number of Alliances

QoG code: atop_number

Number of Alliances Total number of alliances the state is a member of.

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Offensive Obligation

QoG code: atop_offensive

Offensive Obligation 0. Has no offensive obligations 1. Has offensive obligations Coded 1 if the alliance member promises to provide active military support under any conditions not precipit ...

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Commitment start

QoG code: atop_transyr

Transition Year. 1 if any commitment starts or ends in the given year, indicating that some commitment is not in effect for the full year.

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