AbstractIn this preface we introduce the special issue on rainfall‐induced landslides and debris flows. The topic is of high interest for many practical and scientific reasons. In fact, rainfall is the most relevant factor for the triggering of both shallow and deep‐seated landslides, and rainfall analysis is the most frequently adopted approach for forecasting the occurrence of such phenomena. The six papers of the special issue cover most of the key issues relative to rainfall‐induced landslides. Starting from the analysis of these contributions, we identify and discuss, in this paper, several main topics that deserve further research in the field of rainfall‐induced landslide, such as the uncertainty of the data, the quality of geotechnical analysis, the validation of the models, and the applicability of results in the framework of natural hazards. Copyright © 2007 John Wiley & Sons, Ltd.