A green hackathon is a unique occasion when a group of environmentally conscious people comes together to tackle a green issue. PolyU’s Jockey Club Design Institute for Social Innovation joined the Hong Kong Retail Management Association and organized the first HK Green Retail Hackathon on 23 and 24 February 2019. It aimed to bring retailers and young people together to develop ideas that can be applied in retail shops to promote customers' awareness and environmental-friendly practices. 30 PolyU students joined this hackathon along with 50 local university students, and they delivered 30 innovative and green retail ideas with the support of 20 retailers. The Champion, Foodiverse, founded by PolyU students, came up with the ideas to create a reward system to motivate green actions. They received a $30K cash prize and the precious opportunities including UK Workcamp, mentoring and internship programme.