SIPRI: A Comprehensive Guide to Global Peace, Security, Arms and Disarmament
The Stockholm International Peace Research Institute, widely known as SIPRI, is one of the world’s leading independent research institutes working on issues related to international peace, security, armaments, disarmament and conflict. Established in Sweden in 1966, the institute has developed an international reputation for collecting, analyzing and publishing data on subjects that influence global security.
For students, journalists, policymakers, researchers and general readers, its work provides an important way to understand complicated issues such as military expenditure, international arms transfers, nuclear weapons, arms production, armed conflicts and peace operations. Rather than focusing on a single country or region, the institute examines international security from a broad comparative perspective.
Its research is particularly valuable because many questions about military power and international security require consistent data collected over long periods. By maintaining specialized databases and publishing annual research, the organization makes large amounts of information more accessible to the public.
This comprehensive guide explains what the institute is, how it works, what its major databases contain, why its Yearbook is important, how students can use its resources, and what readers should understand when interpreting its statistics.
What Is SIPRI?
SIPRI stands for the Stockholm International Peace Research Institute. It is an independent international research institute dedicated to studying conflict, armaments, arms control and disarmament. The organization was established in 1966 and is based in the Stockholm area of Sweden.
Its work is centered on research rather than military operations or government administration. It collects information from open sources, develops datasets, conducts analysis and publishes research intended to improve understanding of international security.
The institute covers subjects that are closely connected. Military spending can influence arms procurement, arms transfers can affect regional security, nuclear arsenals can influence strategic stability, and conflicts can change patterns of military expenditure and weapons acquisition. Studying these subjects together therefore provides a broader picture of the international security environment.
One of the organization’s distinguishing characteristics is its emphasis on publicly accessible information. Its databases and publications are widely used by academics, journalists, governments, international organizations, civil society groups and members of the public.
History and Establishment
The organization was founded in 1966 in connection with Sweden’s 150th anniversary of peace. Its establishment reflected an interest in creating a research institution capable of examining the causes and consequences of conflict while providing reliable information about weapons and international security.
The first edition of the SIPRI Yearbook appeared in 1969. Over subsequent decades, the publication became an important reference for information concerning military expenditure, arms transfers, nuclear forces, arms production, conflict and arms-control developments.
As international security changed, the scope of research also expanded. Traditional questions concerning nuclear weapons and conventional arms were joined by research into emerging technologies, cybersecurity, space security, artificial intelligence, dual-use technologies and other contemporary security challenges.
The institute’s long historical record is particularly useful because international security trends cannot always be understood through a single year’s statistics. Long-term datasets can reveal changes that may be less visible in short-term reporting.
Major Areas of Research
The research agenda covers several interconnected areas of international peace and security. These areas include military expenditure, arms transfers, arms production, nuclear weapons, armed conflict, peace operations, arms control and emerging security technologies.
Military expenditure research examines how much governments spend on their armed forces and how spending changes over time. This information can help researchers compare defense expenditure across countries and assess broader trends in global military resources.
Research into international arms transfers examines the movement of major conventional weapons between countries. This includes questions about suppliers, recipients, weapon categories and changes in international weapons relationships.
Another important area concerns nuclear weapons. Research examines the size and composition of nuclear arsenals, modernization programs, nuclear doctrines and developments affecting arms control and strategic stability.
The institute also studies armed conflicts and multilateral peace operations. This helps researchers examine how conflicts develop and how international organizations and participating countries respond to them.
Increasingly, research also addresses emerging technologies. Artificial intelligence, autonomous systems, cyber capabilities and outer-space technologies can create new opportunities as well as new security challenges. Understanding these developments has become an increasingly important part of contemporary security research.
SIPRI Military Expenditure Database
The Military Expenditure Database is one of the organization’s most widely used resources. It provides historical information on military spending for countries around the world, allowing researchers to examine expenditure across different periods and economies.
The database includes military expenditure measured in several ways. Depending on the research question, users can examine figures in local currency, current US dollars, constant-price measures and as a percentage of gross domestic product.
This distinction is important. A country’s military spending may increase in nominal terms because of inflation or currency changes without representing an equivalent increase in real purchasing power. Researchers therefore need to select the appropriate measurement before comparing countries or time periods.
Military expenditure can also be examined as a share of GDP. This provides an indication of the relative economic burden of military spending, although it does not by itself explain whether spending is sufficient for a country’s military objectives or whether it produces particular strategic outcomes.
According to the latest 2026 data, global military expenditure reached approximately $2.887 trillion in 2025, representing a 2.9 percent increase in real terms compared with 2024. The figures demonstrate why long-term military-spending datasets are important for understanding global changes in defense resources.
International Arms Transfers Explained
The Arms Transfers Database records international transfers of major conventional weapons. Its historical coverage extends from 1950 through the most recent complete calendar year.
Unlike a database that simply lists the financial value of weapons contracts, the system uses a statistical measure known as the Trend-Indicator Value, or TIV, to help track trends in the volume of international arms transfers.
TIV should not be interpreted as the actual monetary price paid for weapons. Instead, it is designed to facilitate comparisons of trends in international transfers over time.
The database allows users to investigate relationships between suppliers and recipients, weapon categories, delivery periods and other characteristics of major arms transfers. This makes it useful for research into defense procurement, regional security and international military relationships.
The latest update, released in March 2026, incorporated data covering arms transfers through 2025. The associated research reported that the global volume of major arms transfers between states increased by 9.2 percent during 2021–25 compared with 2016–20.
Such figures require careful interpretation. An increase in weapons transfers does not automatically establish why governments purchased weapons or what political consequences will follow. Statistical evidence describes patterns, while understanding causes requires additional political, economic and historical research.
The SIPRI Yearbook and Its Importance
The annual Yearbook is among the organization’s best-known publications. It provides an extensive overview of international security developments, armaments, disarmament and arms-control issues.
The publication brings together research on subjects including military expenditure, arms production, international arms transfers, nuclear forces, armed conflicts, peace operations and weapons-control efforts.
The 2026 edition continues this tradition while addressing contemporary security questions involving emerging technologies and changing strategic conditions. The Yearbook is useful because it combines quantitative datasets with analytical chapters that place those figures in a wider international context.
For students, the Yearbook can serve as a starting point for research papers and essays. A student studying international relations, defense studies, political science, history or peace studies can use its data to identify trends before examining academic literature and primary documents in greater depth.
The publication is also valuable for understanding terminology. Concepts such as arms control, disarmament, military expenditure, nuclear deterrence and arms transfers can have different meanings in different contexts. Carefully reading methodological explanations helps prevent statistical misunderstandings.
Nuclear Weapons and Strategic Stability
Nuclear weapons are another major component of the institute’s research. Its assessments examine global nuclear arsenals and developments involving nuclear-armed states.
Research into nuclear weapons is not limited to counting warheads. Analysts also examine modernization programs, delivery systems, stockpile structures and changes in nuclear policy.
The distinction between deployed warheads, stored weapons and retired but intact warheads is important when interpreting nuclear statistics. A simple total can conceal significant differences in how arsenals are structured and maintained.
Nuclear research also intersects with arms-control agreements and strategic stability. Changes in one country’s capabilities can influence how another country evaluates its security requirements. This can contribute to arms competition or affect negotiations designed to limit nuclear risks.
Because nuclear information can be sensitive and sometimes difficult to verify, researchers must pay close attention to methodology and uncertainty. Public estimates are not necessarily identical to classified government assessments.
Arms Production and the Global Defense Industry
Another important research area concerns the international arms industry. The global defense sector includes companies that manufacture aircraft, ships, missiles, armored vehicles, electronic systems and other military equipment.
The organization’s Arms Industry Database provides information about major arms-producing and military-services companies. This allows researchers to examine the commercial side of international defense capabilities.
Arms production is closely connected to government procurement. When states increase defense budgets, companies may receive larger contracts, expand production capacity or invest in new technologies. Conversely, changes in procurement priorities can affect defense industries and supply chains.
Recent research has shown significant growth in revenues among the world’s largest arms-producing companies. However, company revenue figures should not automatically be equated with government military expenditure. They represent different economic measurements and should be analyzed separately.
Understanding the defense industry is increasingly important because modern military capabilities depend not only on national armed forces but also on complex international industrial and technological networks.
Peace Operations and Conflict Research
International peace operations are another area covered by the organization’s research. Peace operations can involve military personnel, police, civilian experts and international organizations working in environments affected by conflict or instability.
The Multilateral Peace Operations Database provides information on operations conducted since 2000. It includes information such as personnel participation, country contributions, fatalities and budgets.
These datasets can help researchers examine how international involvement in conflict zones has changed over time.
Peace operations should not be understood solely through troop numbers. Their mandates, political environments, resources and relationships with local actors can all influence their activities and outcomes.
For students studying peace and conflict, combining quantitative data with case studies can provide a more complete understanding of international intervention and conflict management.
How the Data Is Collected
A major feature of the organization’s research is its reliance on open-source information. Researchers use publicly available government documents, company information, reports, publications, media sources and other materials.
The use of open sources allows the organization to build datasets that can be examined and discussed by researchers outside government institutions.
However, open-source research also has limitations. Governments may publish incomplete information, definitions can differ between countries and some defense-related information may remain confidential.
Methodology therefore matters greatly. A responsible reader should examine definitions, coverage periods, revisions and measurement systems before drawing conclusions from any dataset.
Historical figures may also be revised as new information becomes available. Consequently, numbers from an older publication may differ from the latest version of the same dataset.
Why the Data Matters for Students
Students can use these resources for assignments in international relations, political science, economics, defense studies, history, geography, journalism and peace studies.
For example, a student researching military expenditure can compare spending trends across several countries over a defined period. A student examining arms transfers can investigate how procurement patterns changed before and after a major geopolitical event.
The key is to use the data as evidence rather than treating a statistic as a complete explanation.
A strong academic paper normally combines quantitative evidence with historical context, government documents, scholarly literature and clearly defined research questions.
Students should also distinguish between correlation and causation. If military expenditure increases at the same time as geopolitical tensions, the statistical relationship does not automatically prove that one caused the other. Establishing causation requires additional evidence.
Understanding the Limitations of SIPRI Data
No international dataset should be treated as perfectly complete. Defense and security information can be difficult to measure because governments use different accounting practices and some information is unavailable.
The military expenditure database, for example, relies on information that may vary in transparency and classification between countries. Researchers therefore use methodological rules to improve comparability.
Arms-transfer statistics have another important limitation. The TIV system is designed to measure trends in the volume of transfers rather than the actual financial value of transactions.
Similarly, estimates of nuclear arsenals involve uncertainty because governments do not disclose every detail of their nuclear programs.
These limitations do not make the data unusable. Instead, they show why responsible interpretation requires attention to methodology, definitions and uncertainty.
SIPRI and International Security in the Modern Era
The international security environment has changed considerably since the institute was established. Traditional military capabilities remain important, but modern security discussions increasingly involve cyber operations, artificial intelligence, autonomous systems, outer space, biotechnology and other technologies.
These developments create new research challenges because the boundary between civilian and military technology is sometimes difficult to define.
Artificial intelligence, for example, can be used for civilian productivity while also having potential military applications. Satellite technology can support communications, navigation and environmental monitoring while also playing important roles in defense systems.
Research institutions therefore increasingly need interdisciplinary approaches that combine international relations, technology studies, economics, law and security analysis.
The continuing expansion of research into emerging technologies reflects this changing security environment.
How General Readers Can Use the Information
General readers do not need advanced knowledge of international relations to benefit from these resources. A useful approach is to begin with a specific question.
For example, instead of searching broadly for information about global military spending, a reader could examine how worldwide expenditure has changed over a particular decade. Instead of asking whether arms transfers are increasing, the reader could examine a specific region or category of weapons.
Readers should also check the year of the dataset. Security statistics are updated regularly, and older figures may be revised.
It is equally important to distinguish between factual data and interpretation. A database may show that military expenditure increased, but explaining why it increased requires additional evidence.
This distinction is particularly valuable when reading news reports. Headlines sometimes simplify complex datasets, while the underlying research may contain important qualifications.
Why SIPRI Remains Relevant
The continued importance of this research institution comes from the need for reliable information about international security. Military spending, weapons transfers and nuclear capabilities can have major implications for international relations, yet much of the underlying information is complex and difficult to compare.
Long-running datasets provide historical context. Annual publications provide updated analysis. Open-source methodology allows outside researchers to examine and use the information.
The combination of historical continuity, quantitative data and contemporary analysis makes the institute a useful resource for understanding global security developments.
For students and general readers, perhaps the most important lesson is that security statistics should be interpreted carefully. Numbers can identify trends, but they do not independently explain political motivations, strategic decisions or future consequences.
Frequently Asked Questions About SIPRI
What does SIPRI stand for?
SIPRI stands for the Stockholm International Peace Research Institute, an independent international institute established in Sweden in 1966 that researches conflict, armaments, arms control and disarmament.
What is the main purpose of SIPRI?
Its main purpose is to conduct research and provide data and analysis on international security, military expenditure, arms transfers, nuclear weapons, conflict, peace operations and disarmament.
Is SIPRI a government organization?
No. It is an independent international research institute based in Sweden. Its research relies heavily on open sources and is intended for researchers, policymakers, journalists and the public.
What is the SIPRI Yearbook?
The Yearbook is an annual publication covering international security, armaments, disarmament, military expenditure, arms transfers, nuclear forces, armed conflict and related subjects.
What does the SIPRI Arms Transfers Database measure?
It records international transfers of major conventional arms and provides information about suppliers, recipients, weapons, orders and deliveries. Its statistical TIV measure is designed to track transfer trends rather than represent actual transaction prices.
Why is SIPRI data important?
Its long-running databases provide standardized information that researchers can use to study global military spending, arms transfers, nuclear forces, arms production and peace operations over time.
Conclusion
The Stockholm International Peace Research Institute has become an important source of publicly available information about international peace and security. Since its establishment in 1966, its research has expanded alongside changes in the global security environment.
Its databases provide historical information on military expenditure, major arms transfers, arms production and peace operations, while its annual Yearbook brings together research and analysis on broader security developments.
For students, its resources can support academic research and help explain complex international-security questions. For journalists and general readers, the data can provide useful context for understanding developments in military spending, arms markets, nuclear capabilities and conflict.
At the same time, statistics should always be interpreted with attention to definitions, methodology, uncertainty and historical context. A figure can describe a trend without explaining its cause or predicting its consequences.
Understanding how the data is constructed is therefore just as important as knowing the number itself. Used carefully, these resources can help readers develop a more informed understanding of the forces shaping international security, arms control and the pursuit of peace.
In an international environment where security issues are increasingly connected to economics, technology, diplomacy and conflict, reliable research remains essential. The institute’s continuing work provides a structured way to examine these developments through data, historical comparisons and independent analysis.