Within the framework of the CCES1 project ‘Climate Policy making for enhanced technological and institutional innovation’ (ClimPol) we are investigating the role of firms in climate policy making. The aim of this research is to give recommendations for effective climate policy design. On the one hand, we address the acceptability of climate policy instruments, on the other hand we study the effectiveness of the institutional framework with regard to the influence of private interest. The influence of firms on the elaboration of climate policy in a democratic system is quite controversial. Firms do not form a solid bloc of opponents to environmental regulation. Some firms even expect to gain from such regulation, either because they offer goods and services that will allow other firms to comply with the regulation or because they are in a better position to comply than their competitors. Some forms of environmental regulation protect incumbents against new entrants (Brau and Carraro, 2004). As a result, the detailed features of climate policy (e.g. exemptions, technological assistance, targeted subsidies) are more important than the general thrust. Firms and industry sectors could try to influence those features rather than oppose the policy upfront. Based on the logic of microeconomic theory and the related work of Robert Falkner (2008) we want to test for business conflict in Swiss climate policy, e.g. among technological leaders and laggards, along the supply chain and between nationally and internationally operating firms. The data for the empirical analysis are drawn from documentation of the consultation process on the Swiss CO2 law in 1994, 1997, 2004 and 2009. Comparing the arguments of industry and peak industry associations over time we check for our hypotheses on business strategy and business conflict and draw a landscape of private interest groups in Swiss climate policy. The arguments of the business associations are compared with the policy discourse in Swiss Parliament in order to investigate potential coalitions for a network analysis of Swiss climate policy. In Switzerland, voluntary approaches are a very common tool to address ‘new’ policy issues (Baranzini and Thalmann, 2004). The Swiss CO2 law and the Swiss Energy law provide a broad framework for the implementation of voluntary initiatives. Several economic sectors as for instance the cement industry, other energy intensive industries and the Swiss car importers have negotiated voluntary accords with the Swiss government – with different levels of success. In a case study based on interviews with the Swiss car importers, we assess the efficiency and effectiveness of voluntary agreements in Swiss climate policy.