The extranet is a key way for the T&G to communicate with its 800,000 members.
Andrew Murray, director of campaigns and communications at the T&G, said: "Rippleffect was the only new-media company that could offer such a broad range of services that satisfied the national requirement of our membership."
The extranet allows union staff to communicate internally and with its members externally, particularly in the promotion of membership benefits.
Rippleffect managing director Ben Hatton said: "The T&G recognised that it needed to use web-based technology to communicate securely with its members. The system we are developing will be user friendly, allowing even those with limited IT skills to be able to access and exchange information."
Rippleffect, which has offices in Liverpool and Manchester, has clients spanning public and private sectors ranging from Everton FC and Living Ventures through to the North West Regional Assembly.
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