We have studied the effect of selectively dissecting the lateral (LGE) and medial (MGE) ganglionic eminences of the striatal primordium on the yield of DARPP-32-immunoreactive striatal neurones in serum-free cultures maintained for 2 or 5 days. The LGE cultures yielded an approximately four-fold higher number of DARPP-32-positive neurones compared with the MGE cultures, without an accompanying difference in total cell numbers. In both types of culture, there was a 70% reduction in DARPP-32 positive neurones from 2 to 5 days in vitro. In conclusion, the LGE is a rich source of striatal precursors and the present culture system provides a good model for the study of factors that may prevent striatal neuronal death.