In recent years there has been a relative lack of innovation in cooling sock technology. Additionally, based on the customer reviews of many of the high-performance cooling socks currently available on the market, many do not exhibit a true cooling sensation. The goal for the Gildan Cooling Sock Commercialization project is to develop a high-end athletic cooling sock by optimizing performance and cost. Using last year’s senior design cooling sock team’s final prototype as our starting point, we first established a definition for cooling. Then, we moved on to conducting testing on the previous team’s prototype, specifically sweating manikin foot testing. By testing these socks against industry-leading benchmark samples, we came to the conclusion that we wanted to implement different technical yarn combinations in a three plaited structure for our first set of prototypes. Next, we outlined the testing procedures we could accomplish through TPACC and the senior design lab to collect data to show the improved performance of the modified cooling socks. One of the challenges associated with establishing a sound testing methodology was identifying an assortment of two-dimensional tests to analyze a three-dimensional garment. Through communication with class professors, TPACC, and Gildan, we selected MMT, Modified WATson, Qmax, and drying tests to assess various aspects that contribute to cooling. We then moved to prototyping using two new technical cooling yarns, and produced prototypes using the Lonati sock knitting machine at the ZTE Knitting Lab. Through this process we learned more about the manufacturing process and some considerations that should be made to improve manufacturing feasibility. Lastly, in our second round of prototypes we implemented a thinner sock design and reincorporated the channel design from the original pattern, which establishes a mind to function connection and enhances the aesthetic of the sock.