Most radiocarbon dates for the earliest Neolithic cultures of west Mediterranean Europe are on samples of unidentified charcoal. If only results obtained on short lived samples (seeds, shells, and bone) of diagnostic material (domesticates, artifacts, and human remains) are considered, then the dates for the first appearance of the Neolithic package are indistinguishable statistically from central Italy to Portugal and cluster around 5400 calendar B.C. This rapidity of spread, no more than six generations, can be best explained in the framework of a maritime pioneer colonization model. cardial ͉ Neolithic ͉ radiocarbon A sound dating of the first appearance of agro-pastoral economies across Europe is a basic prerequisite to the evaluation of how, why, and when hunter-gatherer adaptive systems eventually disappeared from most of the continent in prehistoric times. The task, however, has not proved easy. Before the advent of accelerator mass spectrometer (AMS) radiocarbon dating, bulk samples of charcoal, bone, or shell had to be used, and in many instances the resultant dates were at odds with archaeological expectations based on stratigraphy and typology.