售对于企业来说可是个重头戏。除了要把握各种交易会的机会、面对面的推销外，还要寻找任何可能的机会，给那些潜在的客户写推销信，让对方对自己的产品感兴趣，从而可能有面谈的机会、交易的希望。
促销信分为两种：一种是直接推销产品的信，另一种是答复对方咨询产品的信。如何答复买方的咨询我们前面已经讲过，现在我们着重要讲的是直接推销产品的促销信。
和其他推销方式比起来，促销信成本低廉，还可以传递更多、更详细的产品信息。下面是写促销信应遵循的一些基本原则：
1. Emphasize the benefits rather than the features of the product or service.
2. Use active voice in picturing the reader enjoying the use or performance of the product or service.
3. Focus on one of the main appeals.
4. Subordinate the price, unless it is an obvious bargain, by mentioning it after most of the benefits have been listed.
5. Use a promotion piece (eg. An enclosed brochure) to illustrate the details of the product or service.
6. Specify the action by providing the ways of obtaining the product.