 Wacklin, the water and wastewater companies for climate mitigation. Climate change is aggravating the challenges that water and wastewater utilities face around the world. Many regions now experience more floods, more droughts, and a lower quality of water resources. Utilities have to deal with higher costs and their operations face higher disruptions. At the same time, utilities also contribute to climate change. They cause indirect emissions from electricity consumption, direct greenhouse gas emissions during operations, and other indirect emissions that are a result of utility services. But there is an opportunity. Wacklin, the water and wastewater companies for climate mitigation initiative, supports utilities on the path towards climate neutrality while engaging governments and the international water and climate community. Water and wastewater utilities can reduce their energy consumption by increasing pump efficiency and producing energy from water and used water. We can reduce the carbon footprint by reusing treated wastewater and recycling nutrients. At the same time, we adapt to climate change by making better use of our resources like reducing water losses and reusing water. Water and wastewater utilities become more sustainable and play a leading role in climate mitigation while adapting to climate change. Implementing such measures allows utilities to reduce their operational costs, their services to the public improves, and the environment benefits. Inspired by the pilot project, the Wacklin initiative is spreading this way of thinking and acting to inspire other utilities around the world to strive towards carbon neutrality.