A recently completed landmark study of mathematics and science education in more than 40 countries gathered information that can help address questions about why students in one country do better than students in another. Results from the Third International Mathematics and Science Study (TIMMS) will be released beginning in the fall of 1996 through the spring of 1998. This brochure outlines what such international studies can help us learn, how this study was conducted, and what the United States and other countries might be able to glean from TIMMS. A timeline for the release of the TIMMS data and directions about whom to contact for further information is included. The ideas of intended and implemented curricula are discussed, and a number of related questions that TIMMS may answer are listed. (DDR)