This thesis, done in a capstone course through the Arizona State University School of Sustainability, examines the current state of sustainability-related processes at all of Major League Baseball's Cactus League sites, with a focus on Salt River Fields. Through this close examination, a final report created of our findings and suggestions were presented to executives from Major League Baseball and the two occupants of Salt River Fields: the Arizona Diamondbacks and the Colorado Rockies. The overall goal is to add value to Cactus League stadiums, clubs, and the fans while promoting sustainable initiatives and creating lasting change. With a team of 11 undergraduate and graduate students from ASU led by Colin Tetreault, research was conducted by examining similar efforts by major sports leagues and comparable organizations. Our team researched reports from organizations such as the National Hockey League to determine how we could implement our ideas on a large scale successfully. Determining that fan engagement is crucial to changing the culture and implementation of sustainability, we also researched ways to interact with fans on social media and cooperated with the social media teams from the Arizona Diamondbacks and the Colorado Rockies. Additionally, we visited every stadium in the Cactus League and met with representatives from each team to determine what sort of processes they have in place, if they have any suggestions or thoughts for our efforts, and we gave each of them advice as consultants. At each site, we also interviewed vendors, cleaning crews, and fans for more information. At Salt River Fields, we engaged the guest service attendants, social media team, vendors, the Jani King custodial team, and staff involved with operations for information and to suggest changes. We started a new initiative in cooperation with these entities known as the "Recycle Rally" where we engaged with fans about recycling information and collected their recyclables. Additionally, we surveyed fans on their personal views on sustainability at each game we attended. We also conducted two waste audits at Salt River Fields, where we examined a large sample size of waste, sorted all of it into categories, and weighed it on a scale to determine how much of each category of waste there was. This data was later plotted and analyzed.