At the end of February, thousands of cleaning workers in Minneapolis marched in whats believed to have been the first union-authorized climate strike in the United States. The protesters, many of them immigrants and people of color who have seen their communities harmed by everything from air pollution to drought, wanted their employers to take action on climate change.

Employed by more than a dozen subcontractors, these workers clean corporate buildings that are home to major companies like Wells Fargo and United Health Group. Their demands ranged from a guarantee of more environmentally friendly cleaning products to funding for a green technician janitorial training program, which could help them push for more substantial changes during their day-to-day operations rather than wait for top-down measures.

Employee activists like those in Minneapolis are on the rise. And unlike the traditional union focus on better pay, benefits and working conditions, theyre pushing for something even bigger for companies to align with their values when it comes to one of the worlds biggest issues . Namely, climate change.

As public concern about global warming has risen, companies had already come under pressure from investors , shareholders and consumers to adopt more ambitious climate-related targets for their operations and products. But now that pressure is also coming from within. A recent survey of 375 global executives found that 4 out of 5 companies expect an unprecedented rise in workplace activism over the next three to five years with sustainability and climate change an increasing concern .

While strikes and walkouts may still be the most high-profile forms of employee protest, workers are also taking their efforts online and connecting with those in other departments to amplify their voices. In November, thousands of Google employees signed a letter circulated online demanding that the company take more aggressive action on climate change.