Organizing is the process of creating politically active constituencies out of people with problems by focusing on their strengths and the solutions embedded in their experience. It is the basic work of progressive social change. For groups that are new to organizing, it is most important to define a clear constituency and a systematic plan for involving people. Having a clear but flexible structure, in which people can become leaders but not get permanently attached to a position, will help make the effort inclusive. For groups that have already been organizing for a long time, it is important to review the organization’s constituency, structure, and culture during all strategic planning processes, so the group can be deliberate about expanding or deepening its work. Experienced groups tend to become complacent about and limited in their outreach; they work mainly among already established leaders and activists rather than continuing to expand their base. Groups that combine organizing with services need to be completely clear about the differences between their various strategies, what they are trying to get out of each, and how they will deal with potential conflicts between the two. The illustrations in this chapter show that organizational forms must be crafted creatively, with transparent structures and cultures that are actively shaped by members. Today’s organizations, built through systematic outreach, will form the backbone of the next mass movements, which are already emerging to deal with issues like abuses by global capitalism, the prison industry, war, attacks on civil liberties, and environmental degradation.