In spite of the climate finance commitment by the developed countries to mobilise jointly 100 billion USD per year by 2020 to address the needs of developing countries from a wide variety of sources, there is no clear agreement on the types of funds that might count as mobilised by developed countries and what private finance flows could be considered as mobilised for climate action in developing countries.This study identifies ten considerations that are key to estimating mobilised private climate finance. An example methodology is proposed for tracking mobilised private investment and the methodology is tested on three Nordic case studies. Through the further refinement of methodologies, it should be possible to develop common systems for M&E of finance enabling a clearer understanding of the finance landscape and the effectiveness of interventions for mobilising private investment.