This paper re-examines and attempts to expand current scholarly knowledge concerning correct performance practices for sixteenth-century Spanish vihuela music, with a focus on the Tres Libros de Musica en Cifras para Vihuela by the vihuelista Alonso Mudarra. The study is organized into five areas: fretting and temperament, stringing, technique, rhythm and tempo, and ornamentation. The study on fretting, based on an analysis of Mudarra's music for signs of either meantone or Pythagorean temperament, presents evidence pointing towards the Tres Libros' use of a meantone temperament, as well as a practical approach to the use of a meantone fretting in performances of Mudarra's music. The results of this analysis are compared to conclusions reached in similar studies of Luis Milan's El Maestro. Evidence of use of meantone temperament in Enriquez de Valderrabano's Silva de sirenas is also quoted. The study on stringing challenges the current scholarly assumption that all vihuelists used unison-strung basses. A case for some use of octave-stringing by vihuelists is presented via re-interpretation of literary evidence in Diego Pisador's Libro de Musica and Juan Bermudo's Declaracion; comparisons to stringing on the viola da mano, Renaissance guitar, and Renaissance lute; and an examination of fingerings in Mudarra's Tres Libros and Miguel de Fuenllana's Orphenica lyra. The study on technique attempts to determine the probable use of thumb-out or thumb-under technique by each of the vihuelistas and discusses the technical and musical implications of Mudarra and Milan's use of dedillo. The study on rhythm and tempo focuses primarily on the suitability of extempore rhythmic liberties described in Thomas Sancta Maria's Libro llamado Arte de taner Fantasia in performances of music by Mudarra. Similarly, the study on ornamentation describes and examines the suitability of ornaments given by sixteenth-century Spanish theoreticians, such as Luys Venegas de Henestrosa and Juan Bermudo, for use in the performance of music from Mudarra's Tres Libros.