The Scottish government is to support legislation to make period products available free of charge to all.
Labour MSP Monica Lennon put forward a bill at Holyrood aiming to tackle "period poverty" across Scotland.
Ministers had previously opposed it, citing worries about deliverability and cost, but came under pressure from charities and womens' groups.
The SNP will now vote for the bill at stage one, before seeking amendments to to allay their "significant" concerns.
Ms Lennon said she was "very thankful" to ministers for "listening and responding to the overwhelming public support for the bill".
The legislation would create a legal duty on the Scottish government to ensure that sanitary products are available free of charge "for anyone who needs them".
However ministers initially opposed the bill, with Communities Secretary Aileen Campbell telling MSPs that it could cost more than £24m per year to deliver.
A number of charities and campaign groups voiced disappointment about this, with Girlguiding Scotland saying the "vital" legislation would "not only create economic benefits to individuals and families, but will also support girls and young women's participation in education and extracurricular activities, and help to end the stigma around periods".
The legislation might have proceeded even without SNP backing, with MSPs from Labour, the Conservatives, Greens and Lib Dems all on board.
Ms Campbell has now confirmed that the Scottish government will back the legislation when it comes before parliament for the first time later in February, before seeking "agreement on amendments that will allay our concerns".
She said the government had "significant and very real concerns about the practicality and deliverability of the bill in its current form", but accepted that there was a "broad consensus about general policy objectives".
The minster said regulations would be brought forward straight away to embed existing provisions for free period products in schools in law.
Ms Lennon said: "This is a victory for all of the campaigners and activists who have backed this legislation.
"Scotland has already taken important steps towards improving access to period products and tackling stigma. Legislation will guarantee rights, ensure that current initiatives continue in future on a universal basis, and will help us achieve period dignity for all."