This book describes the palaeography, orthography and morphology of the 14th century saga manuscript Möðruvallabók . First pubished in 2000, it is the third and final volume of a set of which the first 2 volumes were published in 1987, The descriptions are complete and frequencies are given in absolute numbers. Where variation is found between sagas, each saga is treated separately. Möðruvallabók is a large manuscript in size (200 leaves of 34x24cm) and in scope, containing 11 sagas, amomg them Njála, Eigla and Laxdæla. The normalized spelling found in 19th century grammars and dictionaries is based on the orthography found in this and contemporary manuscripts.