The nature of skill acquisition has long been of interest to music educators. This study considers the research context for relationships between aural dictation, sight singing, performance and composition skills. Then, relationships between these skill areas are quantitatively investigated using data from the Australian New South Wales Music 2 2010 and 2011 HSC examination tasks, which take place in the final year of secondary schooling. The results from the HSC data were analysed in three ways: raw results for each isolated skill, correlation analysis for each skill combination and comparative analysis of only top-achieving students. The study found that the highest correlations were between aural dictation and sight singing. Further analysis of top achieving students found that high achievement in multi-part aural dictation was the best predictor of high achievement in the other skill areas.