Purpose: Knowledge sharing contributes to the success of an organization in various ways. This paper aims to summarize the findings from past research on knowledge-sharing outcomes in organizations and to suggest promising directions for future research. Design/methodology/approach: There was a conduction of a systematic literature review that consisted of three main phases: defining a review protocol, conducting the review and reporting the review. The thematic analysis was conducted on 61 studies, based on which a framework for understanding the impacts of knowledge sharing was developed. Findings: Previous research has investigated knowledge-sharing outcomes at three levels: the individual, team and organization; specific impacts are summarized for each level. The most commonly studied factors affected by knowledge sharing are creativity, learning and performance. Knowledge sharing is also found to have some beyond-convention work-related impacts, such as those on team climate and employees' life satisfaction. Research on the outcomes of knowledge sharing is dominated by quantitative studies, as we found only one qualitative study in this review. Based on the discussion of the results, promising avenues for further research were identified and a research agenda was proposed. More research on differential, psychological and negative impacts, as well as interactional and methodological aspects of knowledge-sharing, is suggested. Originality/value: To date, no systematic review has been conducted on the impacts of knowledge-sharing. This paper makes an important contribution to knowledge-sharing research, as it consolidates previous research and identifies a number of useful research topics that can be explored to advance the field, as well as to establish the evidence-based importance of knowledge sharing.