The nature of the relationship between Neanderthals and early modern Homo sapiens is controversial, yet it is fundamental to our understanding of early human evolution. The Middle Palaeolithic sites of Israel are critical to this debate, because unlike those of western Europe and Africa they contain both Neanderthal (at Tabun and Kebara for example) and anatomically modern hominids (as at Skhul and Qafzeh). Here we present new mass spectrometric 230Th/234U dates for dental fragments from the Middle Palaeolithic burial sites of Tabun, Qafzeh and Skhul. These data, combined with published ages from electron spin resonance (ESR), provide compelling evidence that the Tabun Neanderthals and Qafzeh early modern Homo sapiens were approximately coeval in the southern Levant some 100 +/- 5 kyr ago, but indicate that some of the Skhul material is younger. The study also shows that combined mass-spectrometric 230Th/234U and ESR dating is an invaluable technique for dating archaeological sites beyond the range of radiocarbon dating.