This volume deals with binary nitrogen-hydrogen compounds having two, three, or more nitrogen atoms (with the exception of hydrazine) and with compounds composed of nitrogen, hydrogen, and noble gases. The important species containing two nitrogen atoms, N2H, N2H+, N2H2, and N2H3 are described in the first part of this volume. Next, chains and cycles consisting of three nitrogen atoms are covered. Among them hydrogen azide or hydrozoic acid, HN3, is the most extensively studied nitrogen-hydrogen compound described in this volume. With increasing number of nitrogen atoms, the thermochmical stability declines. There is, however, a considerable amount of information on molecules with up to nine linked nitrogen atoms. Several of these binary nitrogen-hydrogen compounds could only be isolated in the form of organic derivatives. In that case, data available for the organic derivatives were included if they were characteristic for the particular unsubstituted N-H parent compound.