The National Institutes of Health (NIH) Library has developed a Web-based training program in response to feedback obtained from a customer survey on learning preferences. A majority of the participants surveyed preferred Web-based training over hands-on training, seminars, printed guides, and personal tutorials. Participants reported that they felt overwhelmed by the amount and complexity of information and that they did not need or want to know how to use all resources simultaneously, but would rather learn how to use a resource when the need arises. Taking these user requirements into consideration, the Library's Instruction Team designed and implemented Web tutorials to meet the users' desire for convenience and the ability to learn at their own pace from anywhere at anytime. Using a Web-authoring tool called ViewletBuilder, the team developed practical, task-specific animated demonstrations or viewlets that show a user how to use library-supported databases or software. Viewlets supplement animation with text balloons and notes explaining the actions to the viewer. Watching a viewlet is like watching a real-time demonstration with navigation buttons for the user to control the speed of the tutorial, allowing the viewer to work at his or her own pace. With Web-based training the NIH Library has been able to deliver a 24/7 learning solution that is both convenient and relevant to the users' information needs in a research environment. (Contains 18 references.) (Author/MES)