Scotland could soon face the spectre of uncollected rubbish piling up in the streets and schools being shut due to strikes.
Thousands of council workers north of the border have now voted to take industrial action after rejecting a pay offer of 2%.
Staff at schools, nurseries and waste and recycling centres throughout the country took part in the strike ballot.
Schools across Scotland could be shut when children are due to return after the school summer break in August.
Unions say action could leave waste piling up in the streets if workers did not get a pay increase of more than the 2% being offered.
Unison's Johanna Baxter told the BBC: "Cosla leaders meet on Friday and must put an improved offer on the table if we are to avoid large-scale disruption to council services across Scotland.
"Council workers south of the border on Monday were offered a flat rate uplift of £1,925, which for those on the lowest pay equates to a 10.5% increase. You have to wonder why council workers north of the border have only been offered a measly 2% increase when the cost of living continues to spiral.
Flat rate payment
"Unison has been calling for a flat rate payment to help those on lower incomes. Most council workers earn less than £25,000 per year."
Unison, Unite and GMB had urged members to vote to strike after Finance Minister Kate Forbes refused an offer of "last-ditch talks".
The unions said they had called for a summit with Ms Forbes and First Minister Nicola Sturgeon in a bid to avoid strike action.
Ms Forbes wrote to Unison last month and said "it would not be appropriate to interfere in these negotiations, given their devolved nature" and "respectfully declined" a meeting proposed by Cosla, the local-authority body.
GMB Scotland senior organiser Keir Greenaway said: "The 2% that's already been massively rejected is a shameful proposal - it's worth less than a tenner a week extra for those earning £25,000 or under, and it will turn a cost-of-living crisis into a catastrophe for many workers and their families.
"Two years ago, these workers were applauded on the doorstep by political leaders, but now they are being told to suffer massive real terms pay cuts ahead of a brutal winter with forecasts of double-digit inflation and annual energy bills over £3,000.
"Our members are angry and scared, and the prospect of tens of thousands of council workers falling into the growing ranks of the working poor is not something GMB is prepared to leave unchallenged."
Matter for Cosla
A Scottish Government spokesman told the BBC: "Pay settlements for council workers - excluding teachers - are a matter for Cosla and are determined through negotiations at the Scottish Joint Committee (SJC).
"As it is not a member of the SJC, the Scottish Government cannot directly intervene in pay negotiations, which are for the trade unions to negotiate with Cosla.
"The Scottish Government urges all parties to continue dialogue and seek a resolution which avoids industrial action."