Through line advertisement agencies and clients have switched to an Integrated Communication Approach, or through the line approach. In the Through line advertisements agencies approach, a mix of ATL and BTL are used to integrate a marketer's efforts and optimize returns from these separate investments.
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Through the line advertising (TTL) is where by mass advertising is used in forming a prospect or customer database that can be implemented for direct marketing activities. An example of this would be an advertisement on TV which features a toll-free number for driving direct contact with new clients or customers.