Advertising Agency

agency which creates campaigns to publicize and promote products

An advertising agency or ad agency is a service business dedicated to creating, planning and handling advertising (and sometimes other forms of promotion) for its clients. An ad agency is independent from the client and provides an outside point of view to the effort of selling the client's products or services. An agency can also handle overall marketing and branding strategies and sales promotions for its clients.
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Noun
1. an agency that designs advertisement to call public attention to its clients
(synonym) ad agency
(hypernym) agency

a firm specialising in the creation, design and media placement of advertisements, and in the planning and execution of promotional campaigns. See Full-Service Advertising Agency; Limited-Service Advertising Agency.