Engineering education for sustainable development (EESD) has emerged as a significant focus since the early 1990s, driven by the broader integration of sustainable development (SD) across education. SD has gained global attention and support from governments, businesses, and organizations. Still, education for sustainable development is emergent in engineering, and varies globally. Scandinavian countries, for example, have made significant progress in EESD with research and growth in courses and curricula, while the United States has seen more localized efforts. Prior research on EESD has focused heavily on course content and student learning, with far less attention to faculty attitudes and experiences. To advance global integration efforts, this study provides a deeper understanding of faculty engagement with EESD. Drawing on Lattuca and Pollard's (2016) model of faculty decision-making to engage in curricular change, this study compares the perspectives of faculty at two universities, one in the U.S. and one in Denmark, to explore the influences that shape engineering faculty choices to engage in EESD. To operationalize EESD, the study focuses on faculty who incorporate the U.N.'s Sustainable Development Goals (SDGs) in their courses. Denmark and the U.S. were selected because of the wide divergence in national policies and practices relative to SD. The two institutions, however, are similar in engineering program size, research orientation (both very high research), and scope of engineering programs. The research used a case study approach and included interviews with five to seven engineering faculty and two to three key informants at each site, along with available texts such as university mission statements, program descriptions, course syllabi provided by interviewees, and national policies or declarations. Lattuca and Pollard's model posits three levels of influence: external (outside the institution), internal (within the institution and the department), and individual (within the person) Findings suggest that all three categories of influence are present in each case, but the salience of each category, the specific factors within each category, and the interactions across categories differ markedly. Where the Denmark case had a more consistent alignment across the three levels of influence, with a largely top-down direction of influence, engagement in EESD in the US case was largely an individual, bottom-up phenomenon with some alignment to, but limited drivers from the external and internal levels. This study captures the importance of strong external and internal influences in shaping faculty engagement in EESD and underscores the limitations of relying solely on individual influences. The findings highlight the role of national policies and cultural norms in creating a supportive environment for faculty to integrate sustainability into their teaching. Where external influences are limited, institutions need to actively align their vision, culture, and resources with the principles of sustainable development to foster a widespread and consistent practice of EESD. While individual faculty have been shown to act as change agents in the absence of strong external and internal influences, their efforts alone are limited in their impact on the practice of EESD. / Doctor of Philosophy / Engineering education for sustainable development (EESD) has become an important focus in recent years as the concept of sustainable development (SD) has been increasingly integrated into education. Broadly, SD works to meet our current needs without harming future generations, and it has widespread global support from governments, businesses, and organizations. While the idea of teaching sustainable development is becoming more common in engineering programs, its implementation varies around the world. Scandinavian countries like Denmark have made significant progress in this area with research and the development of courses and curricula. In contrast, the United States has seen more localized efforts. Most research on EESD has focused on what students learn in their courses, but with less work exploring why faculty members choose to include SD in engineering courses. To better understand why faculty members engage with EESD, this study looks at the perspectives of engineering professors at two universities: one in the U.S. and one in Denmark. In particular, it explores what influences faculty decisions to include the United Nation's Sustainable Development Goals (SDGs) in their courses. Denmark and the U.S. were chosen for this study because they have very different national policies and practices related to sustainable development. However, the universities in both countries are similar in size, focus on research, and the variety of engineering programs they offer. Data for this study includes interviews with five to seven engineering faculty members and two to three key informants at each university. Documents like university mission statements, program descriptions, course outlines provided by interviewees, and national policies related to education were also collected. Though faculty at both universities talked about influences outside the university, influences within their institutions departments, and their individual beliefs and values, both the specific factors at each level and the interactions between factors varied. In Denmark, strong national and institutional policies, values, and norms in support of sustainable development broadly and EESD in particular were key sources of influence, while in the U.S., where sustainable development is more contested, individual faculty beliefs and commitments were more prominent, though these commitments often aligned with broader institutional values and some external drivers. The study underscores the importance of both external factors, like national policies, and individual factors, such as personal beliefs, in shaping how faculty members integrate sustainable development in engineering. It highlights the role of government policies and cultural norms in creating an environment where faculty feel supported in integrating sustainability into their teaching. When external support is lacking, universities need to actively align their vision, culture, and resources with the principles of sustainable development to encourage consistent teaching of EESD. While individual faculty members can make a difference on their own, their impact is limited without strong external and internal support.