In this FRONTLINE report, correspondent Henry Louis Gates, Jr., a Harvard scholar, explores the gaping chasm between the upper and lower classes of black America and probes why it has happened: "How have we reached this point where we have both the largest black middle class and the largest black underclass in our history?"

His personal essay draws a picture of growing black success along with deepening black despair and argues that black upper classes now have more in common with their white colleagues and peers than with those they have left behind in the inner cities.

Reviewing the thirty years that have passed since the death of Martin Luther King, Jr., Gates shows that while many blacks reaped the reward of the civil rights movement and affirmative action and gained middle class status, just as many were left behind in an expanding underclass of poverty.

The program features interviews with prominent blacks such as Cornel West, William Julius Wilson and Maulana Karenga as well as civil rights veterans like Eldridge Cleaver, Angela Davis and Julian Bond. While they differ on historical interpretation, they all agree that the next phase of the black liberation struggle must be focused on economic deprivation and the class divide.

Throughout the program, Gates intertwines his own life story --growing up in a time "when colored people formed a national community bound together by race"-- and compares the choices he faced as a young man and how they differ from choices young African-Americans face today.

He takes a sharp look at the structural and behavioral issues that have led to lower class blacks falling further behind and candidly assesses violent gangster culture and why personal responsibility is as crucial as structural change to help the underclass.

Gates's journey is a vivid, compelling, thought-provoking portrait of a formerly close-knit African American community now fragmented by a great class divide.