This study investigates the role F0 plays in the perception of prominence in American English. Raw, log and locally normalized measures of F0 were extracted from words in a 35K word corpus of spontaneous speech. Linear regression analyses were conducted to test the strength of these measures as cues to prominence, with prominence based on judgments made by ordinary listeners in real-time auditory perception. The Bayesian Information Criterion was used to further investigate whether these F0 measures cue prominence in a linear or piecewise linear function, corresponding to a linguistic model of prominence as a gradient or discrete feature. The results of this study show that F0 measures are similar to intensity measures in both their strength as cues to perceived prominence, and in signaling a discrete prominence distinction that distinguishes non- or weakly-prominent words from words with greater prominence. Our finding that F0 and intensity cue a discrete prominence distinction is compared with our prior finding that duration and word frequency signal gradient prominence distinctions. This apparent discrepancy is discussed in terms of the dual nature of prominence in English, as an expression of layered metrical (stress) structure in phonology, and as an expression of pragmatic focus.