To prepare for asking her boss for a raise, a woman might want to try negotiating for a free breakfast each time she stays at a hotel.

Practicing negotiation skills like this could help women navigate high-stakes requests at work, where they are less likely than men to request raises or promotions and are more often turned down when they do, said Megan Costello, director of Boston's Office of Women's Advancement.

She hopes to bring negotiating tips, like asking for free breakfast, or wheeling and dealing over meeting times with colleagues, to 85,000 of the city's women through a free two-hour training course on how to negotiate in the workplace.

It is just one way the city is trying to whittle away a national salary gap that leaves female workers making 80 percent of what their male counterparts earn.

And it's another way state and local governments are attempting to reduce the gap, in addition to mandates on employers and protections for workers. Meanwhile, a proposed Paycheck Fairness Act that would expose employers to lawsuits if they offered different salaries for comparable work for reasons other than education and experience remains stalled in Congress.

"We're seeing states like California and Massachusetts and Maryland pass bills that have a lot of similarities to the Paycheck Fairness Act, and we can see states act as pilots and incubate different ideas," said Kate Nielson, a policy analyst with the American Association of University Women (AAUW), a nonprofit that promotes education and equality for women and girls.

Massachusetts, where women earn 83 percent of what men make, a slightly narrower wage gap than the national average, passed the first state law that prohibits employers from asking for job candidates' salary history. A similar measure is expected to be introduced in Congress.

The Massachusetts bill also requires men and women be paid equally for the same work and protects workers from retaliation for discussing how much they get paid.

Groups like the AAUW say deciding how much to pay workers based on what they previously earned hurts women because they were probably paid unfairly in their former jobs.

But opponents of the bill argue that it replicates existing state law, that it won't reduce the wage gap, and that it's likely to hurt small businesses.

The inability to ask about a potential worker's past compensation creates a liability concern for small businesses because potential employees might disclose their existing salary anyway, putting a company in violation of the law, said Elizabeth Milito, a lawyer for the National Federation of Independent Business.

More than any other state, New York has narrowed the wage gap. But even there, women only make 89 percent of men's earnings. No state has been able to close the gap for women completely, though Minnesota has eliminated the pay gap for women in the public sector.

But researchers in Minnesota, where women on the whole make 81 percent of men's income, say closing the gap completely will be impossible until men and women are equally represented in all types of jobs.