Darzin International Company Multidisciplinary Engineering Science Open 3 Serial Number 3 2026 07 01 Engineers’ Perceptions of Sustainable Design Practices in Complex Engineering Systems Engineers’ Perceptions of Sustainable Design Practices in Complex Engineering Systems 1 14 EN Journal Article 2026 02 19 <p>This study aimed to explore how engineers working in Tehran perceive, interpret, and implement sustainable design practices in complex engineering systems. A qualitative research design was employed to examine engineers’ lived professional experiences of sustainable design in multidisciplinary engineering contexts. Twenty engineers from Tehran were recruited through purposive and snowball sampling. Participants had professional experience in civil, mechanical, electrical, industrial, software/systems, chemical, environmental, and infrastructure-related engineering fields. Data were collected exclusively through semi-structured interviews, each lasting approximately 45–75 minutes. Interview questions focused on participants’ understanding of sustainability, design decision-making, trade-off management, organizational constraints, stakeholder expectations, use of sustainability tools, and perceived barriers to sustainable engineering practice. Interviews continued until theoretical saturation was reached. All interviews were transcribed verbatim and analyzed using thematic analysis with the support of NVivo software. Analysis generated five main categories: life-cycle and systems thinking, sustainability as a technical design criterion, trade-off management under complexity, organizational and project-level enablers, and tool/data limitations in sustainable engineering practice. Engineers generally perceived sustainable design as more than environmental protection, emphasizing long-term performance, resource efficiency, maintainability, risk reduction, social responsibility, and economic feasibility. However, participants reported that sustainability was often weakened by cost pressure, fragmented project governance, limited client commitment, insufficient local data, and late-stage integration into design processes. Sustainable design was most feasible when sustainability requirements were embedded early, supported by multidisciplinary collaboration, and translated into measurable engineering criteria. The findings suggest that engineers recognize sustainable design as a necessary professional responsibility in complex engineering systems, but its implementation depends on early systems-level integration, organizational support, credible assessment tools, and alignment between technical, economic, environmental, and social objectives.</p> https://jmesopen.com/index.php/jmesopen/article/download/57/53