Zappos.com, which generates more than 60% of revenues from repeat customers, is sending all employees to the equivalent of a customer service boot camp.

Last June Zappos, No. 45 in the Internet Retailer Top 400 Guide to Retail Web Sites, introduced a new customer service program that requires all employees to undergo a four-week training exercise. So far about 75% of the company’s more than 300 employees in Las Vegas have completed the program, says CEO Tony Hsieh.

During the first three weeks of the program, new employees learn the company culture, the customer service program, the inventory management system and work with a more experienced employee in the customer contact center. The final week of the program, employees are sent to Zappos’ Louisville fulfillment center where they pick, pack and ship orders and perform other inventory management tasks.

Rather than commit large amounts of time and money to interactive marketing, Zappos likes to invest in better customer service programs, Hsieh says. We started the program in June as a way to train employees about our culture and how we handle customer loyalty, says Hsieh. Now we are to the point where all our employees are taking the course.

Hsieh says the customer service boot camp helps Zappos weed out potential employees who won’t be a long-term fit for the company. Cross-training also helps existing employees learn new skills and learn about other job functions. The program is a good screening tool, says Hsieh. Better customer service training is beginning to make a big difference.

Zappos begins a new training class every two weeks, says Hsieh. While it’s important for new and existing workers to learn systems and the corporate culture, the biggest plus of the new customer service program is teaching employees how to build stronger rapport with new and repeat shoppers. We’re building a business model that’s all about service, says Hsieh.

In 2005, Zappos grew its web sales 101% to $370 million from $184 million in 2004.