The investment of an individual in education is very important issue. The problem is to determine the optimal lifetime path of education for an individual, who can divide his time between learning and working. Any individual is assumed to act in an optimal way. The optimal schooling level is determined when the marginal return to schooling equals its marginal cost. In the recent decades, different types of human capital models for the education have been developed to analyze this critical problem. In this book, some further extensions of the discussed problem will be presented. This remarkable book emphasizes empirical evidence to the case of Egypt.