AMSTERDAM—U.S. cities won’t be the only places where lab coats and science-inspired signs will fill the streets on 22 April. Groups in eight European countries have announced “solidarity marches” in support of the U.S. March for Science, to be held on Earth Day. Some of the rallies will take place on the same day, whereas others don’t yet have a firm date.

Marches are in the planning stages in the United Kingdom, France, Germany, Switzerland, Ireland, Norway, Belgium, and the Netherlands. Bigger countries may see several; in the United Kingdom, for instance, there are already plans to march in London, Edinburgh, and Manchester. In Norway, researchers plan to take to the streets in Oslo and Trondheim. (There will be marches in New Zealand and Australia as well.)

"We are thrilled," a spokesperson for the U.S. March for Science says in an email to ScienceInsider. "The Women's March really changed the game here. The second this march was announced we began getting emails from cities all over the world with people planning on satellite marches. At this point, the Washington march and rally is a small part of a larger movement, which is exactly as it should be."

In France, 22 April is hardly ideal, because it’s the eve of the first round of voting for the French presidential election. “But we plan to do it that day anyway,” says astrophysicist Olivier Berné of the Research Institute in Astrophysics and Planetology in Toulouse, a member of the organizing group. The idea for a march coalesced on Twitter, just as it did in the United States, Berné says. French scientists routinely demonstrate against declining budgets and a lack of job opportunities, and some of the organizers of the April protest are experienced, Berné says. Frances’s main march will be in Paris, but there are also plans for marches in Lyon, Toulouse, and Montpellier; Berné says the group is seeking support from scientific organizations and societies.

The proliferation of marches is happening as non-U.S. scientists are increasingly debating how to respond to the Trump administration—and, in some cases, taking action. More than 5000 people have already signed a pledge to boycott academic conferences in the United States in response to Trump’s executive order halting the flow of refugees and suspending immigration from seven majority-Muslim countries. An Australian anesthesiologist announced on Twitter that he would stop reviewing papers for U.S. journals. Many others, however, think boycotts would harm U.S. science and would be counterproductive.

Meanwhile, the European Molecular Biology Organization in Heidelberg, Germany, has set up the Science Solidarity List, where scientists can offer bench or desk space to colleagues stranded as a result of the measures. More than 480 researchers in dozens of countries have made offers; it’s not clear whether there have been any takers.

*Update, 3 February, 5:30 a.m.: The list of countries has been updated to include New Zealand and Australia.