This study was designed to determine a pitch skill hierarchy for string sight-reading, to determine the effects of key on string sight-reading achievement, and to determine the validity of a tonal pattern system as a measurement of melodic sight-reading skill for string players. High school string students (n = 94) obtained a mean score of 27.28 out of 31 on a modified version of the Vocal Sight-Reading Inventory. Success rates ranging from 0.99 to 0.72 were established for 31 pitch skills, grouped into eight tonal categories. Significant differences were found between skills appearing in the keys of D and E, with 11 of 31 skills obtaining significantly differing results by key. A 0.95 correlation between note-by-note and skill-based scoring systems indicates that skill-based scoring is a valid measurement of string players' sight-reading of tonal pitch skills within a melodic context. Researchers should explore whether these pitch skills hold their relative difficulty level with less accomplished players and between instrument types, establish a hierarchy for rhythm skills, further investigate the effect of key, and identify anxiety levels for sight-reading when the consequences of performance quality vary. (Contains 2 tables and 2 figures.)