The purpose of this paper is to provide managers, researchers, and consultants with insights into the ways communities of practice (CoPs) simultaneously support organizations' product refinements (their knowledge exploitation and alignment thereof to today's business demands) and the search for and discovery of new products (knowledge exploration and adapting it to changes in the business environment). The research design is based on a four-year longitudinal case study of five CoPs within a specialty chemicals division of a multinational company. Primary (interviews, direct observation) and secondary (internal documents) data were collected and analyzed, resulting in several findings on the role of CoPs in supporting organizational ambidexterity by simultaneously exploiting existing knowledge (aligned to the current business) while exploring new knowledge (adaptive/reactive to business environment changes). The main conclusion drawn from the study is that supporting organizational ambidexterity involves switching between different degrees of managerial involvement in CoPs, namely "aligned" and "adaptive" modes. Alignment results in knowledge exploitation that supports "product refinements", while the adaptive mode leads to knowledge exploration that supports the "search & discovery of new products". The findings are based on a single case study of a firm that used CoPs successfully to support product refinements and search for new products across its R&D teams. Hence, generalizing these results would require analyzing additional cases. The paper provides managers with practical recommendations on how to align CoP dynamics with an organization's specific needs to simultaneously exploit and explore new knowledge. On the one hand, CoPs require a great deal of autonomy to generate a search for and discovery of new ideas or knowledge. On the other hand, managers can and should steer CoP activities when their alignment to business and product refinement is required. The data, approach, and analysis are all original. This paper enriches existing theory as it fulfills an unexplored gap between CoPs and organizational ambidexterity. In this respect, CoP and organizational ambidexterity theories are all enriched.