This brief describes a pathway for operationalizing Climate Appropriate Portfolios of Tree Diversity (CAPTD) that are portfolios of tree species for planting necessary to respond to climate change and other challenges. Seven steps in the pathway to operationalization are presented, including investing in tree seed and seedling systems. Through CAPTD, climate change mitigation and adaptation can be properly factored into tree planting. The brief is most useful for project managers, policy makers and planners wanting to understand how best to intervene to support climate change mitigation and adaptation in tree planting, including in tree seed and seedling supply.