This volume brings together the most important general linguistic writings by Mikołay Kruszewski (1851-1887), whom Roman Jakobson described as "one of the greatest theoreticians of language among the world linguists of the late nineteenth century". Apart from reissuing a revised version of the late Robert Austerlitz’ translation of the theoretical introduction of Kruszewski’s Master’s thesis on morphophonemic alternation in Old Slavic, first published in German in 1881, the bulk of the present volume consists of the first translation ever, by Gregory M. Eramian, of Kruszewski’s doctoral thesis, Outline of Linguistic Science, supervised by J. Baudouin de Courtenay and submitted in Russian at the University of Kazan in 1883, which until now has been available only in German translation, published in Techmer’s "Zeitschrift" (Leipzig, 1884-1890; reprinted Amsterdam, 1973). Together with a detailed introduction, a full list of Kruszewski’s writings, a bibliography of secondary sources, including a reconstruction of the major works consulted by Kruszewski, and detailed indexes of biographical names, subjects & terms, and languages cited for examples, the present volume provides Western scholars with a solid textual and contextual basis for a proper reassessment of the ideas of arguably the most outstanding 19th-century linguistic thinker.