Flagship was hired after a review of former agencies. BLIL, which is funded by the London Development Agency and managed by Serco, provides information, advice and assistance to London firms.
BLIL PR and communications manager Anthony Noun said: 'The work of Business Link in London is crucial to SMEs in the capital, particularly in such tough economic conditions. We feel confident that Flagship will gain maximum exposure for these three initiatives.'
Flagship's people and the workplace division will promote the organisation's rapid response service, which provides support to businesses affected by the recession.
Other projects include a recognition event for a Jobcentre Plus scheme to help long-term unemployed start a business, and the launch of an online social enterprise toolkit aimed at would-be social entrepreneurs.
All three campaigns will focus on raising awareness of the schemes and their benefits through thought leadership research and success stories.
Last year, Business Link in London appointed Mandate Communications to promote its services to the capital's small businesses in the wake of the credit crunch.