This paper compares information synthesis to literature review and meta-analysis as tools for the researcher trying to summarize published information and identify information gaps on emerging technologies. Because information synthesis is narrowly focused and addresses the question of what is not known, as well as what is known, it is a good precursor to a full-scale technology assessment. An example of information synthesis is given, comparing cost-effectiveness of extracorporeal shock wave lithotripsy to two other treatments for kidney stones.