The document discusses the concepts of the "head" and the "long tail" in relation to social entrepreneurship. The head refers to large, scaled organizations, while the long tail refers to many smaller, niche social enterprises. While there is a focus on scaling up head organizations, the long tail has great potential aggregate impact due to the large number of small enterprises. Both the head and long tail approaches have benefits and risks, such as generic vs. niche solutions, and there is a question of how to effectively support the long tail while allowing for cooperation between the two approaches.