Central to the brief is explaining how HomeStart has reorganised its network of family support schemes. Following the revamp, trustees at its 337 local schemes no longer have financial or legal liability.
Comms manager Annie O'Brian said: 'People are often put off involvement because they are worried they may be held liable if anything goes wrong. It's important to ensure people understand [the restructure].'
HomeStart is particularly keen to attract trustees from different sectors, she added. 'They could be in PR or marketing, HR, finance or management,' she said.
Upward Curve will target national and business media and co-ordinate regional activity in the build-up to the campaign's June launch, said MD Helen Ashley.
The catalyst for 'We're asking' was research by the National Centre for Volunteering, in which 11 million people said they would take on volunteer work if asked.
The campaign will be supported by advertising and marketing.
Upward Curve won the account after a three-way pitch. The charity has previously used Geronimo Communications.