Business and liberal elites have long invested in developing collaborative leadership. In Occupy Wall Street and beyond, grassroots progressives are now getting into the game of working together.

Something huge is happening in this country. It’s been a long time since we’ve seen this level of populist activity directed at the right targets: the big banks and the corporate elites that dominate our political system.

But there’s something else going on, behind the scenes. Though largely obscured by the Occupy Wall Street story, we are seeing a rare and welcome level of unity: progressive groups are maintaining a better level of coordination than at any time in recent memory. It’s a trend toward cooperation that should be recognized and celebrated.

With the Occupy protests, it’s been wonderful to see a wide range of labor, community and nonprofit groups come together to embrace the struggle – even though the activists who launched the new movement embody very different organizational cultures. When New York Mayor Bloomberg threatened to evict the Zuccotti Park demonstrators a couple of weeks ago, AFL-CIO president Rich Trumka declared that his federation “Stands with Occupy Wall Street” and encouraged union members to help protect the occupation from a police raid. For their part, Occupy activists have supported workers organizing at companies including Sotheby’s, Wal-Mart and Verizon. Historian and Nation writer Jon Wiener calls it an alliance of “hard hats and hippies.” And it’s not just labor. An impressively diverse coalition of community groups and nonprofit advocates have marched in solidarity as well.

But the kind of cooperation that’s been on clear display in the past month thanks to the Occupy movement didn’t come out of nowhere. In fact, coordination among progressives has been quietly growing for over a decade.

That the labor movement so readily signed on to support the Occupy protests is in part a result of collaboration and networking that began in the 1990s. Cooperation around trade issues – beginning with the fight against NAFTA – served as an important opportunity for labor, community, environmental, student and faith-based organizations to start forming relationships.

The coalition building exploded into view with the 1999 protests in Seattle. There, a “Teamsters and Turtles” coalition famously shined the spotlight of public scrutiny on the World Trade Organization. Global justice demonstrations were another instance in which labor might have kept activists coming from different organizing cultures at arm’s length. But John Sweeney and other union leaders instead threw labor’s institutional weight behind the protests. Many of the relationships that are fostering more fluid and open cooperation now were forged during that time.

Considering coordination among today’s groups, I would make three observations about the recent trend toward progressives playing well with others.

First, cooperation is a product of necessity. One reason we’re coming together is we have to. Divided, we get our butts kicked. Yet, tough times do not guarantee unity. In the 1970s and early ’80s, progressive groups too often fell into infighting when confronted with challenges. In contrast, we’re now channeling our frustrations and grievances into collaborative action. That’s a change for the better.

A second reason groups are working together better is that there are younger leaders at the table. A new generation of leadership, in unions and beyond, is dispensing with some of the old grudges that inhibited cooperation and viewing collaborative action as a vital part of their work. Individuals such as Mary Kay Henry at Service Employees International Union, George Goehl atNational Peoples’ Action and LeeAnn Hall of the Alliance for a Just Society are thinking beyond their own organizations. They’re recognizing that working across boundaries is critical to gaining strength.

Finally, we have seen an institutional investment in building relationships and encouraging collaboration among progressives – an area of focus that for too long has been the domain of elites. In the 1970s, John Gardner, who helped found both Common Cause and the American Leadership Forum (ALF), identified a crisis of leadership in the country. This, he believed, resulted from a dearth of influential figures working across disciplines and organizational divides in pursuit of the common good. Since then, groups like ALF have channeled resources into networking across boundaries. However, their efforts primarily targeted high-level business leaders and prominent individuals in civil society such as university presidents.

Only recently have institutions emerged that are investing resources in this type of activity for social movement activists. Groups such as the Rockwood Leadership Institute should be commended for devoting resources and attention to the challenge of building relationships and encouraging collaboration among progressives. They have created the space for grassroots leaders to come together, understand one another’s interests and learn common skills and practices. The importance of cultivating collaborative action in this way can hardly be overstated.

From the Madison protests of early 2011 to the Occupy movement today, we are seeing the fruits of a new push for cooperation. The lesson of such mobilizations is clear, and we can only hope that a greater number of people working for social change take it to heart: The more we break down barriers and join forces, the more we build power.

Amy Dean is co-author, with David Reynolds, of “A New New Deal: How Regional Activism Will Reshape the American Labor Movement” and is president and founder of ABD Ventures. She worked for nearly two decades in the labor movement and now works to develop new and innovative organizing strategies for social change organizations. You can follow Amy on Twitter at @amybdean, or she can be reached via www.amybdean.com.