C-Tests consist of several short texts in which the missing parts of words have to be reconstructed. C-Tests have excellent psychometric properties and are used in many contexts as economical tests of language proficiency. This collection of papers illustrates the state of the art of C-Test research. It focuses on face validity and washback of C-Tests, C-Test performance and intelligence, C-Tests as screening devices for TestDaF and SIMTEST, ROC analyses for relating C-Test scores to the CEFR as well as use of C-tests in the classroom. A special feature of the volume is the editor’s comprehensive C-Test bibliography.