This paper presents a research project conducted by the Department of Information Science in cooperation with the Saarland Museum, the art museum of the Federal State of Saarland, Germany. The study had two aims. The first was to evaluate some methods of usability engineering for the Web, and the second was to evaluate the usability of the Saarland Museum's Web site and improve it. The applied usability engineering methods were an expert-judgment-focused evaluation using heuristic evaluation with the Heuristics for Web Communication and a user-focused evaluation conducting a laboratory test with actual users and the thinking-aloud method. The combination of heuristic evaluation and laboratory testing provided interesting results. The heuristic evaluation detected a vast number of usability problems. The laboratory test confirmed most of these findings as usability problems and added some usability problems that experts did not discover because actual users often have a different perspective. The evaluation led to a re-design of the Web site. Includes two figures and four tables. (Contains 19 references.) (Author)