A comparison of F0 alignment values was carried out for three Arabic dialects (Moroccan Arabic, Kuwaiti Arabic and Yemeni Arabic) using five speakers from each variety. Clear differences found in peak and valley alignments enable separation of Moroccan Arabic from the two other dialects: (1) values of the F0 valley differed significantly, with Moroccan Arabic showing a later synchronisation than Kuwaiti Arabic and Yemeni Arabic; (2) there was variation as to the effect of syllable structure on F0 peaks. The effect is not significant in Yemeni Arabic and Kuwaiti Arabic as the F0 peak is aligned within the stressed vowel in both CV: and CV:C. In Moroccan Arabic, however, the effect of syllable structure is significant: the F0 peak is earlier in closed syllables than open syllables.