Full service agencies
These agencies are involved in planning, creating, producing advertisements, performing research and selecting media. Some full service agencies also provide non-advertising related services including strategic market planning, direct market promotion programs, interactive marketing and web site design, and public relations. The importance of the various functions provided by a full service agency will depend upon the client.
Some very large full service agencies run their own marketing research departments. There are also many professional services with local and national networks which work closely with the agencies, do commissioned research in specific geographic areas, income levels, consumption patterns, product groups, etc.
A full service agency is one that provide a direct relation to the Copywrite, Artwork, production of ads, Media planning etc.
Creative agencies specialize in "creative" or design-based business models and are also known as a "creative boutique". Their basic interest is in the creation of the advertisement or branding. Other ("full-service") agencies offer design in conjunction with media buying. Media agencies concentrate on media buying. (In the 1990s, media and creative were often unbundled in the interests of economies of scale in buying media.)
The client who chooses to use a design only based advertising agency must assume some of the advertising purchasing. These are activities that are routinely handled by an agency with a media buying option.
These agencies specialized in a particular activity of the whole communication process. They may specialize in certain functions (copy, art, media), audiences (minority youth)or industries (health, computers) or in a marketing communication area (direct marketing, sales promotion, public relation). These type of agencies may serve one client only.
In-house advertising agencies
An In-House agency is a team within a company that focuses on selling the company's product; they will handle all aspects of the brand.
Interactive agencies may differentiate themselves by offering a mix of web design / web development, search engine marketing, internet advertising/marketing, or e-business/e-commerce consulting. Interactive agencies rose to prominence before traditional advertising agencies fully embraced the Internet. Offering a wide range of services, some of the interactive agencies grew very rapidly, although some have downsized just as rapidly due to changing market conditions. Today, the most successful interactive agencies are defined as companies that provide specialized advertising and marketing services for the digital space.
The digital space is defined as any multimedia-enabled electronic channel that an advertiser's message can be seen, heard from and understood. The "digital space" translates to the Internet, kiosks, CD-ROMs, DVDs, and lifestyle devices (iPod, PSP, and mobile). Interactive agencies function similarly to advertising agencies, although they focus solely on interactive advertising services. They deliver services such as strategy, creative, design, video, development, programming (Flash and otherwise), deployment, management, and fulfillment reporting. Often, interactive agencies provide: digital lead generation, digital brand development, interactive marketing and communications strategy, rich media campaigns, interactive video brand experiences, Web 2.0 website design and development, e-learning Tools, email marketing, SEO/SEM services, PPC campaign management, content management services, web application development, and overall data mining, and ROI assessment. There are 4 elements for digital media - Digital media Planning, Social Media, Web design and applications and Digital PR.
Search engine agencies
Lately, pay per click (PPC) and search engine optimization (SEO) firms have been classified by some as "agencies" because they create media and implement media purchases of text-based (or image-based, in some instances of search marketing) ads. This relatively young industry has been slow to adopt the term "agency", however with the creation of ads (either text or image) and media purchases (largely for PPC and contextual advertising), these search agencies are technically known as advertising or media agencies. However, SEO (or Organic Search) has traditionally sat separately, usually as a service offered by web development companies. With the increasing reliance of successful SEO on fresh and engaging website content, there are fewer SEO specialist agencies around, this service is increasingly forming part of full service, PR and social media agency offerings.