This empirical project deals with decision-making in the context of International Labour Conventions, the most binding instruments available to the International Labour Organization (ILO). Formulated in a complex bargaining process, conventions are adopted by a qualified majority of the International Labour Conference in which governments, trade unions and employer associations are represented. Conventions may then be voluntarily ratified by ILO member countries. A ratification entails the obligation to ensure the application of the standard formulated in the convention. There are at present 184 ILO conventions on a great number of subjects, such as fundamental workers? rights, working conditions, or social and employment policies. In a first group of studies, we estimate hazard rate models of the individual ratification decision. The determinants of ratification are found to differ across groups of countries. For developing countries, cost considerations (i.e., the fear of a loss of international competitiveness) seem to dominate, while in industrialised countries political variables also matter. Among these, the importance of government partisanship is of particular importance. The second group of studies are concerned with voting behaviour of the delegates to the International Labour Conference. They analyse the determinants of the voting decision: are these the economic interests of delegates' constituents, or do other considerations, in particular the effect of voting on reputation, also matter? We analyse both voting in plenary meetings as well as participation and voting in committees. Research in progress is concerned with the effectiveness of the ILO?s standards. Preliminary findings suggest that up to the early 1990s, there has been no effect of ILO minimum age conventions on the incidence of child labour. To put these results in perspective, other international organisations and regimes apart from the ILO are analysed as well. The project is part of the interdisciplinary research group ?Institutionalisation of International Negotiation Systems (IINS)?, financed by the DFG, Deutsche Forschungsgemeinschaft. As economists, we adhere to a rational choice model of political decision-making. However, the cooperation with lawyers and political scientists will allow us to compare the explanatory power of our approach with that of others, such as cognitive theories.