Collaboration is taking over the workplace. As business becomes increasingly global and cross-functional, silos are breaking down, connectivity is increasing, and teamwork is seen as a key to organizational success. According to data we have collected over the past two decades, the time spent by managers and employees in collaborative activities has ballooned by 50% or more.

Certainly, we find much to applaud in these developments. However, when consumption of a valuable resource spikes that dramatically, it should also give us pause. Consider a typical week in your own organization. How much time do people spend in meetings, on the phone, and responding to e-mails? At many companies the proportion hovers around 80%, leaving employees little time for all the critical work they must complete on their own. Performance suffers as they are buried under an avalanche of requests for input or advice, access to resources, or attendance at a meeting. They take assignments home, and soon, according to a large body of evidence on stress, burnout and turnover become real risks.

What’s more, research we’ve done across more than 300 organizations shows that the distribution of collaborative work is often extremely lopsided. In most cases, 20% to 35% of value-added collaborations come from only 3% to 5% of employees. As people become known for being both capable and willing to help, they are drawn into projects and roles of growing importance. Their giving mindset and desire to help others quickly enhances their performance and reputation. As a recent study led by Ning Li, of the University of Iowa, shows, a single “extra miler”—an employee who frequently contributes beyond the scope of his or her role—can drive team performance more than all the other members combined.

But this “escalating citizenship,” as the University of Oklahoma professor Mark Bolino calls it, only further fuels the demands placed on top collaborators. We find that what starts as a virtuous cycle soon turns vicious. Soon helpful employees become institutional bottlenecks: Work doesn’t progress until they’ve weighed in. Worse, they are so overtaxed that they’re no longer personally effective. And more often than not, the volume and diversity of work they do to benefit others goes unnoticed, because the requests are coming from other units, varied offices, or even multiple companies. In fact, when we use network analysis to identify the strongest collaborators in organizations, leaders are typically surprised by at least half the names on their lists. In our quest to reap the rewards of collaboration, we have inadvertently created open markets for it without recognizing the costs. What can leaders do to manage these demands more effectively?

Precious Personal Resources

First, it’s important to distinguish among the three types of “collaborative resources” that individual employees invest in others to create value: informational, social, and personal. Informational resources are knowledge and skills—expertise that can be recorded and passed on. Social resources involve one’s awareness, access, and position in a network, which can be used to help colleagues better collaborate with one another.Personal resources include one’s own time and energy.

These three resource types are not equally efficient. Informational and social resources can be shared—often in a single exchange—without depleting the collaborator’s supply. That is, when I offer you knowledge or network awareness, I also retain it for my own use. But an individual employee’s time and energy are finite, so each request to participate in or approve decisions for a project leaves less available for that person’s own work.

Unfortunately, personal resources are often the default demand when people want to collaborate. Instead of asking for specific informational or social resources—or better yet, searching in existing repositories such as reports or knowledge libraries—people ask for hands-on assistance they may not even need. An exchange that might have taken five minutes or less turns into a 30-minute calendar invite that strains personal resources on both sides of the request.

Consider a case study from a blue-chip professional services firm. When we helped the organization map the demands facing a group of its key employees, we found that the top collaborator—let’s call him Vernell—had 95 connections based on incoming requests. But only 18% of the requesters said they needed more personal access to him to achieve their business goals; the rest were content with the informational and social resources he was providing. The second most connected person was Sharon, with 89 people in her network, but her situation was markedly different, and more dangerous, because 40% of them wanted more time with her—a significantly greater draw on her personal resources.

We find that as the percentage of requesters seeking more access moves beyond about 25, it hinders the performance of both the individual and the group and becomes a strong predictor of voluntary turnover. As well-regarded collaborators are overloaded with demands, they may find that no good deed goes unpunished.

The exhibit “In Demand, Yet Disengaged,” reflecting data on business unit line leaders across a sample of 20 organizations, illustrates the problem. People at the top center and right of the chart—that is, those seen as the best sources of information and in highest demand as collaborators in their companies—have the lowest engagement and career satisfaction scores, as represented by the size of their bubbles. Our research shows that this ultimately results in their either leaving their organizations (taking valuable knowledge and network resources with them) or staying and spreading their growing apathy to their colleagues.

Leaders can solve this problem in two ways: by streamlining and redistributing responsibilities for collaboration and by rewarding effective contributions.

Redistributing the Work

Any effort to increase your organization’s collaborative efficiency should start with an understanding of the existing supply and demand. Employee surveys, electronic communications tracking, and internal systems such as 360-degree feedback and CRM programs can provide valuable data on the volume, type, origin, and destination of requests, as can more in-depth network analyses and tools. For example,Do.com monitors calendars and provides daily and weekly reports to both individual employees and managers about time spent in meetings versus on solo work. The idea is to identify the people most at risk for collaborative overload. Once that’s been done, you can focus on three levers:

Encourage behavioral change.

Show the most active and overburdened helpers how to filter and prioritize requests; give them permission to say no (or to allocate only half the time requested); and encourage them to make an introduction to someone else when the request doesn’t draw on their own unique contributions. The latest version of the team-collaboration software Basecamp now offers a notification “snooze button” that encourages employees to set stronger boundaries around their incoming information flow. It’s also worth suggesting that when they do invest personal resources, it be in value-added activities that they find energizing rather than exhausting. In studying employees at one Fortune 500 technology company, we found that although 60% wanted to spend less time responding to ad hoc collaboration requests, 40% wanted to spend more time training, coaching, and mentoring. After their contributions were shifted to those activities, employees were less prone to stress and disengagement.

To stem the tide of incoming requests, help seekers, too, must change their behavior. Resetting norms regarding when and how to initiate e-mail requests or meeting invitations can free up a great deal of wasted time. As a step in this direction, managers at Dropbox eliminated all recurring meetings for a two-week period. That forced employees to reassess the necessity of those gatherings and, after the hiatus, helped them become more vigilant about their calendars and making sure each meeting had an owner and an agenda. Rebecca Hinds and Bob Sutton, of Stanford, found that although the company tripled the number of employees at its headquarters over the next two years, its meetings were shorter and more productive.

In addition, requests for time-sapping reviews and approvals can be reduced in many risk-averse cultures by encouraging people to take courageous action on decisions they should be making themselves, rather than constantly checking with leaders or stakeholders.

Leverage technology and physical space to make informational and social resources more accessible and transparent.

Relevant technical tools include Slack and Salesforce.com’s Chatter, with their open discussion threads on various work topics; and Syndio and VoloMetrix (recently acquired by Microsoft), which help individuals assess networks and make informed decisions about collaborative activities. Also rethink desk or office placement. A studyled by the Boston University assistant professor Stine Grodal documented the detrimental effects of team meetings and e-mails on the development and maintenance of productive helping relationships. When possible, managers should colocate highly interdependent employees to facilitate brief and impromptu face-to-face collaborations, resulting in a more efficient exchange of resources.

Consider structural changes.

Can you shift decision rights to more-appropriate people in the network? It may seem obvious that support staff or lower-level managers should be authorized to approve small capital expenditures, travel, and some HR activities, but in many organizations they aren’t. Also consider whether you can create a buffer against demands for collaboration. Many hospitals now assign each unit or floor a nurse preceptor, who has no patient care responsibilities and is therefore available to respond to requests as they emerge. The result, according to research that one of us (Adam Grant) conducted with David Hofmann and Zhike Lei, is fewer bottlenecks and quicker connections between nurses and the right experts. Other types of organizations might also benefit from designating “utility players”—which could lessen demand for the busiest employees—and possibly rotating the role among team members while freeing up personal resources by reducing people’s workloads.

Rewarding Effective Collaboration

We typically see an overlap of only about 50% between the top collaborative contributors in an organization and those employees deemed to be the top performers. As we’ve explained, many helpers underperform because they’re overwhelmed; that’s why managers should aim to redistribute work. But we also find that roughly 20% of organizational “stars” don’t help; they hit their numbers (and earn kudos for it) but don’t amplify the success of their colleagues. In these cases, as the former Goldman Sachs and GE chief learning officer Steve Kerr once wrote, leaders are hoping for A (collaboration) while rewarding B (individual achievement). They must instead learn how to spot and reward people who do both.

Why Women Bear More of the Burden

Consider professional basketball, hockey, and soccer teams. They don’t just measure goals; they also track assists. Organizations should do the same, using tools such as network analysis, peer recognition programs, and value-added performance metrics. We helped one life sciences company use these tools to assess its workforce during a multibillion-dollar acquisition. Because the deal involved consolidating facilities around the world and relocating many employees, management was worried about losing talent. A well-known consultancy had recommended retention bonuses for leaders. But this approach failed to consider those very influential employees deep in the acquired company who had broad impact but no formal authority. Network analytics allowed the company to pinpoint those people and distribute bonuses more fairly.

Efficient sharing of informational, social, and personal resources should also be a prerequisite for positive reviews, promotions, and pay raises. At one investment bank, employees’ annual performance reviews include feedback from a diverse group of colleagues, and only those people who are rated as strong collaborators (that is, able to cross-sell and provide unique customer value to transactions) are considered for the best promotions, bonuses, and retention plans. Corning, the glass and ceramics manufacturer, uses similar metrics to decide which of its scientists and engineers will be named fellows—a high honor that guarantees a job and a lab for life. One criterion is to be the first author on a patent that generates at least $100 million in revenue. But another is whether the candidate has worked as a supporting author on colleagues’ patents. Corning grants status and power to those who strike a healthy balance between individual accomplishment and collaborative contribution. (Disclosure: Adam Grant has done consulting work for Corning.)

Collaboration is indeed the answer to many of today’s most pressing business challenges. But more isn’t always better. Leaders must learn to recognize, promote, and efficiently distribute the right kinds of collaborative work, or their teams and top talent will bear the costs of too much demand for too little supply. In fact, we believe that the time may have come for organizations to hire chief collaboration officers. By creating a senior executive position dedicated to collaboration, leaders can send a clear signal about the importance of managing teamwork thoughtfully and provide the resources necessary to do it effectively. That might reduce the odds that the whole becomes far less than the sum of its parts.