This paper defines and classifies ecosystem services for decision-making. It argues that ecosystem services should be defined based on both their characteristics and the decision context. There is no single classification system that is appropriate for all contexts, as different contexts require different classifications. The paper discusses several classification schemes and their relevance to different decision-making contexts. It also highlights the importance of understanding the characteristics of ecosystems and the services they provide, as well as the benefits they offer to humans. The paper emphasizes the need for a clear and consistent definition of ecosystem services to enable meaningful comparisons across different projects, policy contexts, time, and space. It also discusses the public-private good aspect of ecosystem services, their spatial and temporal dynamics, joint production, complexity, and benefit dependence. The paper concludes that a 'fit-for-purpose' approach is needed in creating classifications, considering both ecological and social contexts. The paper also highlights the importance of considering equity in the provision of human welfare and the distribution of ecosystem services. The paper argues that a consistent and ecologically based definition of ecosystem services is important for future research and conservation assessments.This paper defines and classifies ecosystem services for decision-making. It argues that ecosystem services should be defined based on both their characteristics and the decision context. There is no single classification system that is appropriate for all contexts, as different contexts require different classifications. The paper discusses several classification schemes and their relevance to different decision-making contexts. It also highlights the importance of understanding the characteristics of ecosystems and the services they provide, as well as the benefits they offer to humans. The paper emphasizes the need for a clear and consistent definition of ecosystem services to enable meaningful comparisons across different projects, policy contexts, time, and space. It also discusses the public-private good aspect of ecosystem services, their spatial and temporal dynamics, joint production, complexity, and benefit dependence. The paper concludes that a 'fit-for-purpose' approach is needed in creating classifications, considering both ecological and social contexts. The paper also highlights the importance of considering equity in the provision of human welfare and the distribution of ecosystem services. The paper argues that a consistent and ecologically based definition of ecosystem services is important for future research and conservation assessments.