The purpose of this document is to highlight the impact of the informal sector in select cases and to demonstrate the need for climate practitioners to factor-in the informal economy into climate change mitigation in order to have more inclusive and effective GHG reduction measures. The study starts by examining the informal economic sectors of member states of the Pacific Alliance (Colombia, Chile, Mexico, and Peru) and concludes by showcasing Informality in the Brick Industry, Informal Taxis, Informal Alluvial Gold Mining and Informality barriers to implement Carbon Tax Instruments. A series of discussion questions are then proposed in order to inspire future contributing research on this topic.