The nuclear industry has enormous challenges to address in understanding its waste products and their safe disposal. It is extremely expensive and difficult to work with such waste products. As computational chemistry has made so many advances in the last 30 years, the question arises as to whether it can start to answer some of the basic questions. It was in this context that British Nuclear Fuels plc approached the quantum chemistry group at the University of Cambridge. After initial considerations, it was decided to write an entirely new quantum chemistry package to address these fundamental problems. The MAGIC program has been written to model as accurately as possible the properties of heavy-atom (in particular, actinide) complexes in realistic environments. Major requirements were the need to include relativistic effects for which several investigations have been carried out by quantum chemists in recent years. A severe difficulty is the high angular momentum of the occupied orbitals in the actinides. It was also believed that it was very important to include the effects of electron correlation. Again much progress has been made by quantum chemists with this problem. Therefore this code was written to take into account all these advances in a simple enough way that calculations on realistic systems are possible. The program is the result of a collaboration between British Nuclear Fuels plc and the University of Cambridge. The program has been developed with a view to making the implementation of new ideas as straightforward as possible. Hence, the code has a simple modular structure. Individual modules may of course be combined in a script to run more complicated procedures, such as a self-consistent field (SCF) procedure. The aim of such an approach is to maximize the time spent in the science compared with that spent interfacing with the computer code. For the end user a simple graphical user interface through Cerius# is provided. Standard features of the input may be selected easily from individual menus for each module. It is also possible to access more advanced features. Comprehensive help facilities are available within the interface. Use of the visualization tools helps not only to see the results of calculations on large molecules more clearly, but also to present them in a concise and clear way. The program has been developed on an SG workstation, but it has been extended to run in parallel on a Cray T3E. This paper is the basic paper which describes in detail the philosophy, science and implementation of the MAGIC project. At the end, sample calculations are reported. Furthermore suggestions are made about how this program may, even at this stage, be used to address problems with actinides in the nuclear industry. In order to place the development of the MAGIC project in context and to make adequate recognition of the contribution of others, this article contains considerable material of a review nature, a brief history of the development of quantum chemistry and density function theory, the treatment of core electrons and relativistic effects, the evaluation of integrals, the treatment of solvent effects and the convergence of the SCF iterations. All are written with calculations on actinide complexes as the ultimate goal.