As competing uses of our coastlines increase, natural resource agencies are employing marine spatial planning (MSP) to designate areas for different uses or activities in order to reduce conflicts while achieving ecological, economic and social objectives. A central challenge of implementing MSP is development of a rigorous approach for analyzing tradeoffs across the provision of ecosystem services (i.e., the benefits humans receive from nature). This study develops an operational approach to this problem that is founded on community-based methods, ecological production theory, and multi-criteria decision analysis (MCDA). The approach merges ecological models with surveys to identify marine ecosystem services for use in tradeoff analysis. The approach allows for a single set of marine ecosystem services to at once be valued by local stakeholders and measured by biologists, thus connecting social and biological monitoring efforts. To develop the approach in a real-world context, I examined ecosystem services associated with nearshore marine ecosystems in Oregon, where marine reserves are being introduced for biodiversity conservation. I worked with stakeholder focus groups in three Oregon communities to identify 24 marine ecosystem services. I then linked the ecosystem services with ecological indicators, which I then consolidated to derive 11 items for use in a survey-based tradeoff analysis exercise. I administered the survey to a nonrandom sample of stakeholders in Oregon (n=31), from which their relative preferences and preference weights for ecosystem services were derived. The weights and preference measures may then be used in MSP decision-making. Furthermore, I grouped the stakeholder survey data in three ways: by location of residence (coastal vs. non-coastal), by eight categories of affiliation (e.g., business owners, conservationists, commercial and recreational fishers, etc.), and by resource use patterns. I then analyzed the various groupings of stakeholders for within- and between-group homogeneity of preferences. Results of the analyses showed that there are statistically significant variations in preferences within and between most groupings. Capturing the variations in stakeholder preferences is important when developing policies that affect different stakeholder groups. Thus, when implementing the survey instrument, I suggest random sampling of stakeholders stratified by location, affiliation, and resource use. This study provides one of the first examples of a systems-based approach to ecosystem service valuation operationalized to inform MSP, and novel features of the approach have a number of implications for advancing marine research and management. First, by using stakeholders to identify ecosystem services, the approach allows for a tailored implementation of ecosystem-based management at the community level. Second, by integrating ecological and economic information on the provision and value of ecosystem services, the approach provides relevant data for MSP decision-making during the siting, evaluation, and monitoring stages. And third, by applying both stated-preference and MCDA methods, the approach may capture the array of values represented by diverse stakeholder groups.