The Public and Commercial Services Union (PCS) has been neutral in terms of a Yes/No decision but the union in Scotland has undertaken an extensive consultation which shows strong support for the policies of the Yes campaign and the parties backing that stance.
The public sector union asked a series of 20 questions on workers' issues of representatives of all parties and the Yes and No campaigns. It then ranked the answers with a thumbs up, thumbs down or 'not specified' - with the union only backing one answer from the No campaign.
In contrast, the answers put forward by the Yes side received 16 "thumbs up'" signals from members of the union. The union's Scottish secretary, Lynn Henderson said: "Our position back in February was to take no sides, but as a result of our membership survey we took on key issues.
"If people think it's pro-Yes, that is just how the answers came out."
Deputy First Minister Nicola Sturgeon hailed the result, saying: "This analysis by PCS highlights the opportunities of Yes for our public sector workers - ending austerity and ensuring support for low paid workers.
"The No camp is nothing more than a front for a Tory party which is intent on devastating our public services with its austerity and cuts agenda."