When Being on Too Many Teams Helps – and Hurts

Why It Matters

Many organisations rely on employees working across several teams at once. This study shows that while this can boost short-term performance, it may quietly undermine a team’s ability to adapt when circumstances change.

Key Takeaways

• Being part of multiple teams can improve performance by giving teams access to wider knowledge and networks.
• The same structure can reduce adaptability, as people narrow their roles to cope with overload.
• Teams with diverse internal knowledge are better able to capture the benefits, and limit the downsides, of multi-team working.

Multiple Teams: A Double-Edged Sword

Working across several teams at the same time has become normal in banks, consultancies, technology firms and universities. This way of working promises efficiency: organisations can spread expertise across projects and respond quickly to changing demands. Yet managers often struggle to judge whether this structure actually helps teams perform better.

The research examines this tension by treating multi-team membership not as simply good or bad, but as a trade-off. On the one hand, team members who also work elsewhere bring in fresh information, contacts and perspectives. On the other, dividing attention across teams can drain time and mental energy, pushing people to focus narrowly on what they already know.

Using data from 473 financial analyst teams at J.P. Morgan over nine years, the study tracks how these opposing forces play out in real work settings. The findings show that both effects happen at the same time, and that they affect different aspects of team effectiveness.

Why Performance Improves but Adaptability Suffers

Teams whose members work on several projects gain access to broader external networks. Through colleagues on other teams, they can tap into new market insights, specialist expertise and alternative ways of solving problems. This wider pool of information helps teams deliver high-quality outputs more efficiently, improving performance on defined tasks.

However, the same arrangement makes it harder for teams to adapt when conditions change. To cope with constant switching between projects, people tend to limit the range of roles they take on across teams. Instead of experimenting with different responsibilities, they stick to familiar ones to save time and effort.

This narrowing of roles reduces the variety of experiences that help people recognise when existing approaches no longer work. As a result, teams may be slower to revise their thinking, update their outputs or respond creatively to new challenges, even if they continue to perform well in the short term.

The Hidden Role of Internal Diversity

The study identifies a crucial factor that shapes whether multi-team working helps or harms a team: internal informational diversity. Teams made up of members with varied knowledge, expertise and perspectives are better at processing complex information together.

In such teams, members are more likely to share, debate and integrate insights gathered from outside projects. This strengthens the performance benefits of working across multiple teams, because external ideas are more effectively translated into the team’s own work.

At the same time, internal diversity helps cushion the loss of adaptability. Even if individuals take on similar roles across teams, diverse teams can compensate through discussion and collective sense-making. By pooling different viewpoints internally, they remain better able to adjust when new information or unexpected changes arise.

Business Implications

For leaders, the message is not to abandon multi-team working, but to manage it more deliberately. Assigning people to multiple teams can raise performance, especially in knowledge-intensive roles, but it also creates hidden risks for adaptability.

Managers should pay close attention to team composition. Teams with a broad mix of expertise are more likely to benefit from multi-team arrangements without becoming rigid. Leaders can also rotate roles, create space for reflection, and encourage knowledge sharing to prevent teams from becoming overly specialised.

At an organisational level, the findings suggest that flexibility and resilience depend not just on how many teams people join, but on how teams are designed internally. Multi-team membership works best when diversity is treated as a strategic asset, not an afterthought.

Authors & Sources

Authors: Tingting Lang (Renmin University of China), Thomas A. de Vries (University of Groningen), Haoyuan Li (University of International Business and Economics), and Jason D. Shaw (Nanyang Technological University)

Original article: Academy of Management Journal (2025)

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