The purpose of this study was to investigate how Canadian adult students collaboratively learn with peers in both formal and non-formal adult literacy programs. A multisite case study research design was used involving several local literacy organizations. Data collection occurred over a four-month period and focused on nine different program sites. Six data sources were subjected to various analytical techniques such as constant comparison, direct interpretation, and correspondence and patterns. Findings suggest that collaborative learning can be a foundation that supports a community of practice across tutorial, small group, and large group adult programs. This type of learning involves several key components such as social learning practices, the instructor's philosophy and leadership style, teaching strategies that favor peer collaboration, movement from guided learning to independent learning, and personal agency. Implications of the study for adult literacy practitioners, researchers, and policy makers are discussed. (Contains 1 table and 1 figure.)