The union, the largest in the public sector, says the 'million voices' campaign will be its biggest in 10 years, and will call on the government to put 'people before profit'.
It will include a film, an advertising campaign and a range of regional initiatives.
Unison general secretary Dave Prentis said that the union had chosen now to launch the campaign 'because of the recession and the threat it poses to public services.
'If any part of the economy will get us through these tough times,' he added, 'it is public services and public service workers.'
Unison's campaign comes at the same time as the BMA is pursuing its Look after our NHS campaign against commercialisation in the health service.
- Is Unison right to be spending £1m on this campaign?
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