This research presents a novel approach to supplier selection by integrating economic, environmental, and ethical criteria. The case study of Company 3B, a food production company, illustrates this process. Expert decisionmaking, using a fuzzy-rough approach, is supported by the fuzzy-rough Logarithm Methodology of Additive Weights (LMAW) and the fuzzy-rough modified Measurement Alternatives and Ranking according to Compromise Solution (MARCOS) methods. The fuzzy-rough LMAW method helps determine the importance of criteria, revealing that experts consider the economic criterion the most significant. The Modified MARCOS (M-MARCOS), a simplified version of the MARCOS method, is used to rank suppliers. Results show that Supplier S3 performs the best. These findings are validated through comparisons with other fuzzy-rough methods and a sensitivity analysis. With the MARCOS method comparisons confirming a consistent ranking order, this paper advances supplier selection methodology by introducing a novel approach and improving the usability of the MARCOS method through modifications.