In contemporary supply chains, supplier selection has been extensively studied using Multi-Criteria Decision-Making approaches, while the evaluation of buyers from the supplier’s perspective remains comparatively underexplored. This study proposes an expert-driven multi-criteria decision support framework for bidirectional buyer–supplier evaluation that formalizes both supplier and buyer assessment within a unified structure. Industry experts from FMCG sector were surveyed to identify and weight evaluation criteria using direct weighting and Analytic Hierarchy Process (AHP) pairwise comparisons. The framework integrates AHP, TOPSIS, and VIKOR to comparatively evaluate ranking behavior under different organizational contexts. In addition, the model distinguishes between binary qualification criteria and weighted performance criteria to better reflect real industrial decision practices. The proposed framework is implemented within an interactive decision-support system and evaluated through multiple comparative