The editors are pleased to present to the nuclear com- munity our new-look annual review. In its new look, with Plenum our new publisher, we may hope for a more rapid pre- sentation to our audience of the contents for their consi- deration; the contents themselves, however, are motivated from the same spirit as the first nine volumes, reviews of important developments in both a historical and an anticipa- tory vein, interspersed with occasional new contributions that seem to the editors to have more than ephemeral interest. In this volume the articles are representative of the editorial board policy of covering a range of pertinent topics from abstract theory to practice and include reviews of both sorts with a spicing of something new. Conn's review of a conceptual design of a fusion reactor is timely in bringing to the attention of the general nuclear community what is perhaps well known to those working in fusion - that practical fusion reactors are going to require much skillful and complex engineering to make the bright hopes of fusion as the inex- haustible energy source bear fruit. Werner's review of nu- merical solutions for fission reactor kinetics, while not exactly backward looking, is at least directed to what is now a well established, almost conventional field. Fabic's sum- mary of the current loss-of-coolant accident codes is one realisation of the intensity of effort that enables us to call a light water reactor 'conventional.