[en] There are a number of different technologies for implementing interim storage of spent fuel at reactor sites. It is generally accepted that, if possible, expanding the capacity of existing fuel pools through the installation of compact racks and the use of fuel rod consolidation are the most economical first steps. Once these have been carried out, other alternatives must be employed if further capacity expansion is required. It is not the purpose of this paper to discuss the relative economics of these alternatives, since under specific constraints and conditions each one can be shown to have an economic benefit. However, it is the reduction in plant operations, the minimising of radiation exposure, the inherent flexibility and corresponding overall favourable economics that have led to the development of the dual purpose storage and transport cask in the past few years. (author)