Imagine a world without trash or landfills. Every year, 1.3 billion metric tons of municipal solid waste are thrown away around the world - and that number is expected to increase by 70% by the year 2025. To tackle the issue, a citizen army is gathering. Their motto: the best waste is no waste at all. The idea is to buy only what you need in order to create a virtuous cycle: less consumption, less plastic and less waste. We take a look at how to adopt a zero-waste lifestyle.