The Thesis aims to develop a flexible multi-factorial methodology based on incremental complexity, guiding decision-makers from simple assessments to comprehensive evaluations. The framework integrates three levels: strategic fit, sustainability and utility value, and accommodates both qualitative and quantitative data. Testing across nine case studies in energy, waste, agriculture, and industry sectors at multiple governance levels confirmed its adaptability and effectiveness in identifying sustainable solutions. The methodology contributes to informed, inclusive, and sustainability-driven decisions, supporting circular and climate-resilient development.