The value of travel time savings (VTTS) is the monetary value attached to the possibility to save a determined amount of travel time. VTTS is also the most important benefit category aimed at justifying investments in transport infrastructures by public administrations. Hence VTTS played a significant role in various economic studies, both analytical and empirical. The present paper introduces a brief history of meta-analysis and describes the microeconomic formula used in VTTS estimations. It also provides a meta-analytical estimation of a selection of empirical studies, emphasizing the similarities and the differences between European and North- American observations.