A microscopic interpretation is proposed for the behaviour of the superconducting transition temperatureTcas a function of hole concentrationpin La2-xSrxCuO4when oxygen vacancies are suppressed. At highp∼ 0.32 a BCS-type formula forTcis assumed, whereas at lowp∼ 0.06 it is proposed that the holes undergo Wigner crystallization. Near the Wigner transition, one has a strongly correlated hole liquid, and Cooper pair binding will become increasingly difficult asp→ 0.06 from above, because the Fermi distribution is strongly changed from the unit step function, appropriate nearp∼ 0.32. Some experiments are proposed to test the microscopic model put forward here.