The document discusses strategies for motivating contributions to online communities based on social psychology theories. It explains that only a small fraction of users actively contribute content, while most are passive. To increase contributions, the document examines personal and environmental motivators like enjoyment, social recognition, and developing a common identity or bonds between community members. It also analyzes how goals, visibility of contributions, and reinforcers like badges could influence participation levels. The document argues that while social science provides useful insights, community design requires balancing factors and outcomes cannot be guaranteed, making it part science and part art.