A comparative evaluation of several pitch determination algorithms (PDAs) is presented. Fundamental frequency estimates, F0, are compared with laryngeal frequency estimates, Lx. An algorithm is presented which enables Lx contours to be generated from laryngograph data. We seek the most accurate method of FO extraction in order to minimise errors propagating into subsequent prosodic analysis. The super resolution pitch determinator [S] performs well relative to the other PDAs studied. Modifications made to this algorithm are described, which radically reduce the number of gross F0 errors and improve the classification of voiced and unvoiced sections of speech. The raw F0 contours produced by this enhanced algorithm are processed to form schematised contours used in computer aided intonation teaching. The series of processes used in the schematisation is described.