The uncontrolled exploitation of Earth’s resources has resulted in irreversible changes in the environment generally and the climate in particular. Therefore, a global and immediate policy response is urgently required to reduce greenhouse gas emissions and mitigate climate change. There is compelling evidence that climate change is the greatest and widest-ranging market failure ever seen. To combat the resultant market failure and externalities, there is a need to tackle climate change through economics. The paper aims at portraying the certainty associated with the economic approaches, rather than the policy approaches for combating climate change. A carbon tax seems to be a potent mitigation policy, other policies being cap and trade, renewable portfolio standards, feeding tariffs, production tax credits. If these policies are implemented exclusive of each other, irrespective weaknesses may cause hurdles, however, if harmonised internationally, they can be effective in promoting clean energy and thereby helping combat climate change. We compare these policies in different countries with a view to comprehensively analysing their respective roles in combating climate change.