Arbetet är uppdelat i tre delar. De första två behandlar koldioxidavskiljning och lagring, CCS, varav den första främst är en intervjustudie som analyserar debatten om CCS i Sverige. Den andra är en ekonomisk utvärdering av CCS vid implementering i massabruk. Massabruken är för övrigt en av Sveriges största källor till koldioxidutsläpp. Den tredje och sista delen behandlar Kyotoprotokollets flexibla mekanismer, nämligen joint implementation, JI, och clean development mechanism, CDM, utifrån hypotesen att stora delar av de beräknade ekonomiska vinsterna kan komma att ätas upp på grund av transaktionskostnader., Focusing on carbon dioxide – Three system approaches on carbon dioxide capture and storage and flexible mechanisms This work is based on the assumption that solutions to the present day problem with carbon dioxide and climate change can be either major changes in behavioral patterns or technical and economical methods. We have decided to analyze the possibilities and weaknesses in the two latter options. The work is divided into three major parts. Part 1 deals with the issue how carbon dioxide capture and storage (CCS) – a technology being developed at present – is perceived by various actors in the Swedish society. CCS can be seen as a continuation of the present path-dependence. A common view is that the market mechanism should be left to make the final decision on the future of CCS. Part 2 is a study on possibilities of CCS in the pulp industry in Sweden. At present there is no powerful enough mechanism in place to reward such drastic carbon dioxide reducing measures. With relatively small overall emissions in Sweden, further reduction potential could however be found in the pulp industry. The question is who will foot the bill. Part 3 is focused on an economic means of addressing carbon dioxide emissions, Joint Implementation (JI), and how it might encounter transaction costs of a discouraging magnitude. To a large extent, transaction costs tend to be country specific, with the highest costs where JI otherwise would have most impact on reductions.