Colony continues the story Ben Bova began in Millennium, following astronaut-turned-administrator Chet Kinsman years later as the head of an orbiting space habitat that has become Earth's only real refuge from a planet buckling under overpopulation, food shortages and unrest. Getting a place in the habitat is a matter of life and death for millions who will never be chosen, and as Earth's governments grow more desperate to control or dismantle the colony outright, Kinsman has to decide how far he'll go to protect the world he's built off-world. Bova later folded both novels together into the omnibus The Kinsman Saga. Part of Ben Bova's Chet Kinsman series.
Summary by Loreful, from public sources