Since caste is at the heart of the problems within Hinduism, this is a classic statement of what to do about it.
B.R.Ambedkar Philosophy of Hinduism
A hard-hitting and eminently scholarly masterpiece that is a must read for a Hindu wishing to be a progressive and make Hinduism progressive. This is not a piece for those Hindus who are insecure in their Hinduism and become defensive immediately.