One of the commitments of World Youth Day (WYD) Lisbon 2023 is related to Sustainability Today, July 3rd, this commitment resounds all the more with the celebration of International Plastic Bag Free Day. This day aims to raise awareness about the excessive production and use of plastic bags worldwide.

With the idea of reducing the need to create new plastic for use, from the beginning, WYD Lisbon 2023 chose to place cardboard labels on all merchandise to avoid using plastic and plastic packaging as much as possible.

WYD Lisbon 2023 also decided to include a reusable ECO water bottle Pilgrim's Kit to encourage more sustainable water consumption. This ECO bottle reduces emissions associated with the production and transport of disposable bottles and reduces waste in landfills and plastic bottles in the oceans. The WYD Lisbon 2023 Volunteer kit will also have this item. Since it is impossible to eliminate plastic completely, all plastic produced by the assembly of the kits is collected and sent directly for recycling.

Another initiative that will be carried out to compensate for part of the environmental footprint generated by all the activities necessary for organizing the largest international gathering of youth with the Pope is worldwide tree planting. The goal is to make WYD Lisbon 2023 an example to follow in the commitment to Sustainability and to leave a positive legacy regarding this issue that is so important to the youth. According to the latest assessment, nearly 17,000 trees have already been planted. Groups and dioceses around the world have already joined the challenge.

In Pope Francis' Encyclical Laudato Si' on Care for Our Common Home, published in 2015, the Holy Father addresses climate change, warning of the need for a "concern for the environment thus needs to be joined to a sincere love for our fellow human beings and an unwavering commitment to resolving the problems of society".