Before joining VU Amsterdam in 2022, I completed my Habilitation at the Technical University of Munich (2020), obtained my PhD at Humboldt-Universität zu Berlin (2012), and held research and teaching positions in Munich, Dresden, and Erfurt, including the interim Franz Haniel Professorship of Public Policy (2017–18).

My research proceeds along two complementary lines. The substantive line examines the domestic politics and politicization of international security: why democracies differ in their involvement in military operations, how parliaments shape decisions on the use of force, and how foreign policy changes under geopolitical transformation, most recently in work on Germany’s Zeitenwende and European responses to Russia’s war against Ukraine. The methodological line advances set-theoretic and multi-method approaches, in particular Qualitative Comparative Analysis (QCA) as a set-theoretic approach to descriptive and causal inference.

My books include Democratic Participation in Armed Conflict: Military Involvement in Kosovo, Afghanistan, and Iraq (Palgrave Macmillan, 2014), which received the Best Dissertation Award of the German Political Science Association, and Qualitative Comparative Analysis: An Introduction to Research Design and Application (Georgetown University Press, 2021 with a second edition under contract), translated into Japanese as 質的比較分析 (QCA): リサーチ・デザインと実践 (Chikura Publishing, 2023). I am also the co-editor of the Routledge Handbook of Foreign Policy Analysis Methods (2023).

I am an editorial board member of International Studies Quarterly, Foreign Policy Analysis, and Contemporary Security Policy. In 2025-2026, I chaired the Committee on Dissertation Completion Fellowships of the International Studies Association (ISA). In 2022, I was elected to serve on the Ethics Committee of the German Political Science Association (DVPW) for a five-year term.

This website gives information on my research, teaching, and other professional activities.