It's when you seek to invest into a business or a venture that has an explicit ambition to do business in a way that respects people and the planet, and when the products and services of this business - as well as their relationship with suppliers are also socially and environmentally conscious.  Ideally, the business tries to create a solution to an unresolved problem and makes its products and services accessible - serves the underserved groups of population. Well, this is the elevator pitch. To get started in defining what matters to you, what positive outcomes you want to contribute to, imagine a sustainable and equitable future. Then think about what enabling factors made that future possible. Based on that, think about what topics are closest to your heart: is it gender equality, empowerment of women, access to education, protecting wildlife or forests? For inspiration, take a look at the UN Sustainable Development Goals. 

The Rockefeller Foundation issued a report recently on the Individual  Imperative: Retail Impact Investing Uncovered. A good read that will hopefully trigger lots of innovation.