There are many ways to gain practice and poise in telemarketing. Many organizations use volunteer phone workers during campaigns and fund drives. One of the most visible of these is public television stations, which conduct fund-raising drives several times a year and are always looking for volunteer help to staff the phone banks. Other groups that routinely need volunteer telemarketers include local political campaigns, theaters and other arts groups, churches, schools, environmental organizations, and nonprofit social organizations, such as crisis centers and inner-city recreation programs.

Telemarketers generally work for one of two types of businesses. Some telemarketers are part of the in-house staff of a company or corporation and make and receive calls on behalf of that company. Others work for a telemarketing service agency and make or receive calls for the clients of the agency. Telemarketing agencies are useful for companies that don't want to or can't keep a full-time telemarketing staff on the payroll or that need telemarketing services only occasionally. Both large corporations and small firms employ telemarketing agencies, which sometimes specialize in particular fields, such as fund-raising, product sales, and insurance.

Telemarketers are generally responsible for either handling incoming calls or placing calls to outside parties. Incoming calls may include requests for information or orders for an advertised product, such as clothing, magazines, appliances, or books. Telemarketers also staff the phones that handle toll-free "800" numbers, which customers call to ask questions about the use of a product or to register complaints. Airline reservations, concert and sports tickets, and credit card problems are all transactions that can be handled by telemarketers. Newspapers often employ classified ad clerks to transcribe classified ads from callers. A person whose sole job is taking orders from callers over the phone is sometimes called an order clerk.

Telemarketers place outside calls for many purposes as well. One of the most important reasons to make such calls is to sell products and services to consumers. The phone numbers of the people that telemarketers call usually come from a prepared list of previous customers, the phone book, reply cards from magazines, or a list purchased from another source. Sometimes randomly dialed "cold calls" are made. Once made, these calls often serve as a source of potential leads for the company's regular sales staff. A wide range of products—from newspaper subscriptions and credit cards to time-share resort condominiums and long-distance service—can be successfully sold in this way. Once a sale is made, the telemarketer records all necessary information, such as the buyer's name and address, product choices, and payment information, so that order fillers can prepare the product for shipment.

Cultural organizations, such as ballet and opera companies, public television stations, and theater troupes, use telemarketers to solicit subscriptions and donations. Charity fund-raising also relies heavily on telemarketing.

In addition to selling, telemarketers make calls for other reasons. They may conduct marketing surveys of consumers to discover the reasons for their buying decisions or what they like and dislike about a certain product. They may call to endorse a candidate in an upcoming election or tell citizens about an important vote in their city council. When making calls business-to-business, telemarketers may try to encourage attendance at important meetings, assist a company in recruitment and job placement, or collect demographic information for use in an advertising campaign.

When making outbound calls, telemarketers usually work from a prepared script that they must follow exactly. This is especially true of market-research surveys because people need to be asked the same questions in the same way if the survey data are to be valid. Often when a customer tries to resist a sales pitch, the telemarketer will read a standard response that has been prepared in anticipation of potential objections. At other times, the telemarketer must rely on persuasive sales skills and quick thinking to win over the customer and make the sale. Telemarketers have to be a little more skillful when selling business-to-business because these customers usually have a clear idea of the needs of their businesses and will ask specific questions related to them.