Here are the thoughts of Sri Srila Prabhupada swamy on Caste System in modern world. There are many classes of men in society—some men are engineers, some are medical practitioners, some are chemists, tradesmen, businessmen, and so on. These varieties of classes are not to be determined by birth, however, but by quality. No such thing as the caste-by-birth system is sanctioned by the Vedic literature, nor do we accept it.
The ultimate goal is to educate people in how to love God. Chaitanya Mahaprabhu approves the conclusion that the highest perfection of human life is to learn how to love God. The Krishna consciousness movement has nothing to do with the Hindu religion or any system of religion. No Christian gentleman will be interested in changing his faith from Christian to Hindu.
Similarly, no Hindu gentleman of culture will be ready to change to the Christian faith. Such changing is for men who have no particular social status. But everyone will be interested in understanding the philosophy and science of God and taking it seriously. One should clearly understand that the Krishna consciousness movement is not preaching the so-called Hindu religion. We are giving a spiritual culture that can solve all the problems of life, and therefore it is being accepted all over the world.
Ref: Chapter 3o, Science of Self Realization authored by Srila Prabhupada (Founder – Acharya, ISKCON). This text is provided by Hare Krishna Movement, Hyderabad.