The small grammar of Old Icelandic is designed as a teaching and learning aid for academic instruction. The work conveys foundational knowledge about the precursors, transmission, and phoneme system of Old Icelandic. The main focus is on inflectional morphology, with a special chapter addressing sound change processes that are relevant for understanding the complex forms of Old Icelandic. Furthermore, the peculiarities of syntax are analyzed. Appendices discuss the characteristics of Old Norwegian, Old Swedish, and Old Danish. A comprehensive bibliography, a word index, and a small lexicon of linguistic terms conclude the presentation. A reader with selected texts and a glossary is in preparation.