Social innovation addresses societal challenges through new solutions, relationships, and ways of thinking. It occurs at micro, meso, and macro levels to meet social needs in a more effective, efficient, and fair way than existing solutions. Social innovation is driven by new actors like social entrepreneurs and requires its own support systems given market failures around public goods. Companies can benefit from social innovation by learning, boosting reputation, and connecting to future markets while also achieving social impacts beyond what governments and non-profits can.