Originally published in 1970 The Theory and Practice of Neutrality in the Twentieth Century documents the various shapes and forms that neutrality has taken. The most important are neutralization, traditional neutrality, ad hoc neutrality and non-alignment. Each of these terms is carefully defined and illustrated by documents running from the beginning of this century to the late 1960s. This enables students to judge for themselves whether neutrality can again become, as it was in the past, an honourable convenience, or whether, except in so far as it contributes to mediation and peacekeeping, it is an anachronism.