This document summarizes a research study on mainstreaming environmental and climate change adaptation into road projects in Cambodia. It identifies several key challenges: a lack of research on climate-resilient road investment; the need to operationalize climate adaptation in project design, assessment, and implementation; and institutional challenges related to resource dependency, decision-making power dynamics, and capacity limitations. The study examines two road projects to analyze how climate risks were considered in environmental assessments and resilience efforts. It finds inconsistencies between the projects and gaps in comprehensively addressing adaptation. Stakeholder interviews revealed that budget constraints, pressure for results, and uncertainty can hamper mainstreaming climate adaptation in practice.