ISO 14001 (Environmental management systems) is an ISO bestseller and for good reason.
It enshrines good management practises, that help us all to protect the environment, and it makes sure a business meets regulations. But a key principle in this document is that it requires an appreciation of the relationship between environmental aspects and environmental impacts. We tend to focus on the impacts but consideration of aspects is just as important.
Environmental aspects are activities that might have an influence on the environment: the what part of the equation if you like. Environmental impacts are the affect of those aspects on the environment.