It’s abundantly clear that microörganisms play an essential role in maintaining the health of humans, animals, and plants. But how exactly they pull this off is still mostly a mystery—one that the White House hopes to help solve by way of a new microbiome research initiative.

Specifically, the White House is proposing a federal investment of $121 million toward microbiome research, to be divided among the Department of Energy, NASA, the National Institutes of Health, the National Science Foundation, and the Department of Agriculture. The high-level goal is to better understand the “behavior” of microbiomes so that we can learn how to maintain or restore the function of healthy ones. Much of the work will focus on developing new scientific tools for teasing out the details of how microbiomes work, and how that varies depending on the particular ecosystem.

In recent years, scientists have taken advantage of inexpensive genetic sequencing and computing power to collect vast amounts of information about the microbes that inhabit humans, animals, and plants as well as soil, bodies of water, and the atmosphere. The research has shown that the health of a given microbiome is in some way linked to the health of its host.

But while we have a pretty good idea of which organisms are present in certain well-studied microbiomes—for example the one in the human gut—little is known about how they interact with each other and with their host. Shedding light on this fundamental question will be essential to developing therapies or other technologies meant to fix dysfunctional ones.

One of the biggest needs in human health is for more long-term studies, said David Murray, director of the office of disease prevention at the National Institutes of Health, during a launch event at the White House on Friday. Information from those studies could help answer fundamental questions, like whether a given health problem leads to a dysfunctional microbiome, if it’s the other way around, or some combination of the two, he said.

As part of this research effort, a number of university research labs and private research foundations announced new efforts to stimulate microbiome research as well. Leading the charge is the Bill and Melinda Gates Foundation, which will invest $100 million over four years and will focus on two main challenges that recent research has suggested are connected to the microbiome: childhood malnutrition and the maintenance of crop health.

Today’s cutting-edge research and technical tools have “so far only provided us a glimpse of the promise that understanding how communities of microbes behave will ultimately hold,” said John Holdren, assistant to the president for science and technology and director of the White House Office of Science and Technology Policy, at Friday’s launch event. Key to the new federal initiative will be collaboration between scientists who study different microörganisms and ecosystems so that disparate threads can be linked together in an “integrated and overarching way,” he said.