This thesis provides a detailed explanation of the complex interrelations between national political dynamics and policy-making processes within the European Union, with a particular emphasis on Germany's involvement in the negotiation of the Corporate Sustainability Due Diligence Directive. The central research question is as follows: What factors influenced Germany's decision to block the CSDD adoption despite agreeing to the proposal just a month earlier? The theoretical approach for this research integrates normative institutionalism and a new model of foreign policy analysis within the framework of two-level game theory. These theoretical constructs are leveraged to dissect the dual-level negotiation processes, facilitating an analysis of how Germany navigates between internal pressures and broader EU policy mandates. This theoretical exploration extends to assess the overarching dynamics of EU legislative processes, especially in relation to the alignment and conflict between economic imperatives and normative policy objectives such as sustainability. Methodologically, this thesis utilises in-depth theory- building process-tracing to identify causal-mechanisms that led from the proposal of the CSDD draft to Germanys decision to hinder the adoption of the agreed upon draft. The results underscore a nuanced landscape of negotiation and adjustment, wherein Germany's economic imperatives frequently conflict with the EU's sustainability ambitions. The analysis demonstrates that Germany's external commitments to EU sustainability policies are significantly conditioned by domestic economic considerations, which in turn influence Germany's tactical approaches within EU policy negotiations.