DraftWorldwide pitched against Black Cat Communications and Heresy to win the work, which includes press, outdoor, direct marketing and web-based activity.
At the heart of the drive is a customer-acquisition strategy, to run alongside the brand awareness activity, which is what gave Draft the edge over its competitors.
Telewest Business head of marketing Clare Grant said: "DraftWorldwide's direct marketing background means it is very data-centric, so it knows about data mining and data segmentation and will work well with our internal team to make sure we're targeting the right audience."
Grant said that the division is looking to raise its profile among "larger corporate multi-size organisations and the public sector". However, she added that it would still support the small business market.
DraftWorldwide will produce a series of campaigns, the first of which will break in the coming months. At the time of writing, details about the creative element of the campaign were not available.
Telewest's business and consumer above-the-line accounts were previously held by Saatchi & Saatchi, which was appointed to the cable operator's consumer and business work in 2000 after it took over content business Flextech.
Telewest Business dropped Saatchi & Saatchi in January last year, and its offline activity was then handled by HHCL-owned agency Heresy on a project-by-project basis.
DraftWorldwide has been working with Telewest Business since last summer when it picked up its interactive advertising account, giving it a head start when the company decided to consolidate its online and offline activity into one agency.
Grant said: "Draft's work for us over the last nine months has been impressive. They have really grasped our requirements and demonstrated a real enthusiasm."
Telewest Business's media planning and buying is held by WPP-owned Media Insight, which has worked on all Telewest's media for more than two years. Speculation has been mounting that this may be up for review, but Grant said that it is continuing to work with the agency.
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