Marketing Intermediaries
Independent firms which assist in the flow of goods and services from producers to end-user; they include agents, wholesalers and retailers; marketing services agencies; physical distribution companies.
Some of which are described briefly below:
Retailers
Retailers operate outlets that trade directly with household customers. Retailers can be classified in several ways:
• Type of goods being sold( e.g. clothes, grocery, furniture) • Type of service (e.g. self-service, counter-service) • Size (e.g. corner shop; superstore) • Ownership (e.g. privately-owned independent; public-quoted retail group • Location (e.g. rural, city-centre, out-of-town) • Brand (e.g. nationwide retail brands; local one-shop name)
Wholesalers
Wholesalers stock a range of products from several producers. The role of the wholesaler is to sell onto retailers. Wholesalers usually specialize in particular products.
Distributors and dealers
Distributors or dealers have a similar role to wholesalers - that of taking products from producers and selling them on. However, they often sell onto the end customer rather than a retailer. They also usually have a much narrower product range. Distributors and dealers are often involved in providing after-sales service.
Franchises
Franchises are independent businesses that operate a branded product (usually a service) in exchange for a license fee and a share of sales.
Agents
Agents sell the products and services of producers in return for a commission (a percentage of the sales revenues)




Reference: http://wiki.answers.com/Q/What_are_%27marketing_intermediaries%27


My opinion: The intermediary are very important for every company specially manufacturing because it adds value to the marketing of the product by bringing in specialization, marketing knowledge, capacity to segment the market, and selling skills which help marketers to implement their marketing strategies effectively. They also increases convenience to both the producer and the consumer by offering effective delivery and pre and post-purchase customer service as well as facilitating manufacturer services.