Labour's 1997 victory was widely credited to the party's reinvention of itself as New Labour. This book argues that the transformation of the Labour Party is best understood as the product of Thatcherism, and marks the emergence of a new consensus in British politics.
Good deconstruction of the rightward shift in the Labour Party and British politics in general since 1979; as the book was written in 2001 or so, it's a good record of attitudes at the time.