We investigated the effects of selective attention and musical training on the processing ofharmonic expectations. In Experiment 1, participants with and without musical training were required to respond to the contour of melodies as they were presented with chord progressions that were highly expected, slightly unexpected, or extremely unexpected. Reaction time and accuracy results showed that when attention was focused on the melody, musically trained participants were still sensitive to different harmonic expectations, whereas participants with no musical training were undifferentiated across expectation conditions. In Experiment 2, participants were required to listen holistically to the entire chord progression and to rate their preference for each chord progression. Results from preference ratings showed that all the participants, with or without musical training, were sensitive to manipulations of harmonic expectations. Experiments 3 and 4 showed that changing the speed of presentation of chord progressions did not affect the pattern of results. The four experiments together highlight the importance of attentional focus in musical training, especially as it relates to the processing of harmonic expectations.