Global manufacturing continues to grow, creating the need for enhanced innovation during New Product Development (NPD); this in-turn requires increased utilization of employee-generated knowledge. Enterprise Social Networks (ESNs), such as Yammer.com, is one method identified which can allow organisations to connect employees across departments and physical boundaries. This paper summarises the results of a dual-moderated focus group conducted with 15 employees of a UK-based sports manufacturer, aimed at identifying the impact of Yammer on employee knowledge generation and sharing during NPD projects. Results indicate that employees see benefit in its use and would welcome greater embeddedness of ESNs in the NPD process. However, barriers are identified which may inhibit its successful deployment, including issues relating to security and intellectual property rights. Identified benefits of using Yammer include: an improved ability to find people with specific domain knowledge; increased awareness of communities of practice; and the matching of problems with solutions.