Book excerpt: This book constitutes the thoroughly refereed postproceedings of the 7th Workshop of the Cross-Language Evaluation Forum, CLEF 2006, held in Alicante, Spain, September 2006. The revised papers presented together with an introduction were carefully reviewed and selected for inclusion in the book. The papers are organized in topical sections on Multilingual Textual Document Retrieval, Domain-Specifig Information Retrieval, i-CLEF, QA@CLEF, ImageCLEF, CLSR, WebCLEF and GeoCLEF.