This deliverable presents a methodology for defining sustainability requirements and its application to eleven use cases, including a mobile network operator (MNO) use case and ten use cases from vertical scenarios agriculture, energy, and e-health. The proposed methodology offers a structured approach for deriving sustainability requirements, beginning with the identification of stakeholders’ sustainability needs, key values, and key value indicators (KVIs), which ultimately enable the formulation of use case specific, vertical specific and cross vertical sustainability requirements. The work presented herein aims to guide sustainability research within SUSTAIN-6G and, more broadly, to bridge the gap between technology development, commercial adoption, and policymaking across the information and communication technology, and vertical industries.