At the behest of the director of the Tierra Madre Horse Sanctuary, three School of Sustainability (SOS) undergraduate interns worked to collaboratively develop a sustainable solution to the sanctuary’s horse manure problem. Guided by SOS staff and graduate students, the interns utilized the Transformational Sustainability Research Methodology approach to frame the project. The Tierra Madre Horse Sanctuary provides a forever home for over 30 abused or abandoned horses, but it previously had no solution for the ever growing pile of manure these horses generated. The interns began by gaining an understanding of the problem by visiting and volunteering at the sanctuary to do onsite research. They were able to define sustainability criteria for assessing the long-term sustainability potential of their suggested interventions. After engaging in an internal visioning exercise, the interns planned and executed a visioning session with the director and four key volunteers. From this, the interns planned and implemented interventions to address the manure problem. Beyond producing a brief report of their efforts, the interns were able to successfully craft and implement the sustainability interventions they envisioned. They also partnered with a local nursery that was happy to compost all of the horse manure and create a system for doing so in the future. At the same time, the nursery invited Tierra Madre to take as much compost as they could use. Additionally, the interns were able to establish a garden at the sanctuary, a key idea which emerged from the visioning exercise. Tierra Madre is a great organization with which future interns could work on gardening and community outreach. Horse manure is a problem which other sanctuaries, boarding stables, etc., face around Arizona and the approach and solutions utilized here could be useful to many, if not all, of them. There is great opportunity to broaden the impact of this important project.