This two-part research project evaluated the effectiveness of interpretive messages at Fossil Butte National Monument in conveying knowledge about the place and its resources and promoting respect for the fossil resource. The first study measured the short and long-term knowledge gains from a trip to the Visitor Center and the influence of a specially designed fossil respect message on the fossil protection beliefs of Monument visitors. The Visitor Center was successful in conveying information about the fossil resource and story of Fossil Lake, and that knowledge was retained for at least several weeks. However, neither the Visitor Center nor the special message, were successful in improving the fossil respect beliefs of respondents. The second study combined a visitor survey with direct observations of visitor behavior to evaluate the effectiveness of interpretive materials along a nature trail in improving the knowledge of ancient Fossil Lake, increasing fossil respect beliefs, and reducing depreciative behaviors. Six different treatments were applied that evaluated an interpretive sign, box of fossils that visitors were invited to touch, and participation in an interactive interpretive program. Only the interpretive program increased knowledge of the Fossil Lake story. None of the trail interpretive materials improved fossil respect beliefs. The sign was somewhat effective in reducing entry into a closed research quarry. While it is generally thought that those most knowledgeable about natural resources will have the higher resource protection beliefs, Fossil Butte visitors who reported being the most interested in fossils had the greatest knowledge of the Fossil Lake story but had the lowest fossil protection beliefs. Therefore, there was some evidence that fossil enthusiasts were the least likely to respect the resource.