Online Learner Collaboration (OLC) supports the development of knowledge and skills through social construction. In this systematic review of research spanning a decade, authors examined 63 articles for publication patterns, participant and context trends, and research methodology trends using an online learner collaboration framework consisting of the following elements: collaborative technologies, design, facilitation, and outcomes. The higher education context and education discipline had the most research conducted on OLC among the studies reviewed. All three research methods (quantitative, qualitative, and mixed methods) were used equally in the articles. The most commonly used technologies for OLC were learning management systems (LMS), discussion boards, writing tools, and synchronous tools. The most commonly used collaborative methods were group projects and discussions. The most common grouping size was small groups, and groups were commonly formed through random assignment, based on criteria, or student-formed. Instructors mostly assumed roles as designers, facilitators, supporters, and evaluators during OLC. Increased learning, communication and collaboration skills, and relationship building were the top three opportunities that OLC offered. Time, technical issues, and anxiety/fear/stress were challenges that appeared most frequently. Most of the research on OLC focused on cognitive and affective outcomes. The review has implications for online instructors and instructional designers who design and facilitate collaborative online courses.