An international, scientifically grounded framework for defining, measuring, assessing, verifying and accounting for changes in ecosystem services.
The Quality Ecosystem Services Standard™ – Framework is the expanded and detailed professional framework of the Quality Ecosystem Services Standard™. It defines general requirements for defining, measuring, assessing, verifying and accounting for changes in ecosystem services, while not forcing different services into a single common physical measurement system.
The ecosystem, its condition, ecological functions and processes, ecosystem services, and human and social benefits are understood as an interconnected system.
The assessment focuses on the attributable change in a predefined ecosystem service.
Each service must be assessed using physical or modelled measurement units appropriate to its nature, with adequate data quality and traceability.
A QESSK™ közös szakmai követelményeket biztosít, miközben a konkrét measurementi módszereket az adott ecosystem service sajátosságaihoz igazítja.
Changes in pollination service can be assessed based on a demonstrable relationship between ecosystem functioning, pollinators and the beneficiary plant population.
Relevant changes in water retention, infiltration, runoff, water quality and other hydrological processes can be assessed from an ecosystem service perspective.
Changes in soil erosion, soil structure, water retention, organic matter content and other relevant soil functions can be assessed as service outcomes.
The basis of service assessment is a change in an ecological function or process and its demonstrable contribution to human or social benefit.
The assessment must identify which people, communities or economic activities receive an identifiable benefit from the ecosystem service.
The physical or modelled service outcome is primary. Monetary valuation is a separate assessment layer and cannot substitute for demonstrating the service outcome.
QESSK™ distinguishes step by step between an intervention and a demonstrated and verified ecosystem service outcome.
Define the affected ecosystem, project and service boundaries, and the relevant spatial and temporal boundaries.
Clearly define the ecosystem service being assessed and the associated beneficiaries.
Identify the activity that maintains, improves, restores or creates the service, and demonstrate its causal relationship.
Define the appropriate reference state and baseline, then assess financial, regulatory, practical and ex-post additionality.
Determine the service change using appropriate data or scientifically grounded modelling, then assess attribution and uncertainty.
Account for displacement, negative effects, net outcome, durability and reversal risk.
The project and service outcome must be assessed by a competent and independent verification body in accordance with QESSK™ requirements.
A properly demonstrated and verified outcome may be accounted for in QESCR™ form after registry-level assessment.
QESCR™ is not a universal physical unit of measurement. It is the standardized accounting form of a defined ecosystem service outcome demonstrated and verified against a reference state with additionality established.
The accounting record must include, among other things, the service, project, site, period, reference state, outcome magnitude, unit, attribution, uncertainty and verification.
The QESCR™ quantity may not exceed the appropriately demonstrated and verified ecosystem service outcome.
QESCR™ is not automatically equivalent to water quantity, area, soil loss or any other universal physical unit.
Accounting must consider, among other things, uncertainty, attribution, data quality, baseline uncertainty, displacement, durability and reversal risk.
QESSK™ ensures outcome integrity not through arbitrary correction percentages, but through evidence, attribution, uncertainty management, safeguards and independent verification.
Data accuracy, completeness, timeliness, spatial representativeness and methodological suitability must be managed through documented quality assurance.
The project outcome must be compared with an appropriate counterfactual reference state, and it must be demonstrated that the outcome would not have occurred, or would not have occurred to the same extent, without the project.
It must be assessed whether the project causes negative environmental effects elsewhere or displacement of pressures associated with the outcome.
The expected durability of the service outcome and the risk of its loss must be assessed and appropriately managed.
Unjustified multiple accounting of the same environmental outcome is not permitted. Multiple issuance, accounting, claiming, use and overlapping claims must be addressed separately.
DNSH, human rights, the rights of local and Indigenous communities, land-use and property rights, and appropriate community participation are part of project integrity.
2026 revised and expanded edition · International scope · OurOffset Nonprofit LLC
The 2026 edition provides a common professional basis for assessing changes in ecosystem services, defining the reference state and baseline, assessing additionality, measurement and modelling, attribution and uncertainty management, treatment of negative effects and durability, independent verification, registry-level assessment and QESCR™ accounting.
Request information about access to the full framework documentation, or submit the basic details of your ecosystem service project for preliminary assessment.
Request information about access to the full documentation, professional application, project application or cooperation.
Submit the basic details of your ecosystem service project or programme for preliminary assessment against QESSK™ requirements.