The law was signed by Republican Governor Charlie Baker on Monday, making Massachusetts the first state to pass a law that prohibits employers from asking interviewees about their salary history, keeping them from basing someone’s pay on what they previously made, though anyone can volunteer that information if they so choose.

Think Progress writes that proponents of the law argue that the practice of requiring potential hires to divulge their earlier salaries places women in a cycle of low pay—if a female worker made less than her male counterpart at her last job, she’s more likely to make less in her next role as well.

The bill also prohibits companies from penalizing employees who discuss their salaries with their peers, or “salary secrecy,” a practice that has been outlawed in California and New York as well. Additionally, it requires that both men and women be paid equally for “comparable” work, a provision that was also included in the California law.

Fortune reported earlier this year that the U.K. has also taken a big step to mitigate the situation by publishing companies’ gender pay gaps on a public, searchable website.