The paper states the requirements which the design of electrical accessories for domestic purposes must fulfil and how such requirements can be met. Contacts and switching are dealt with at some length because of their effect upon the performance and life of most accessories. The fundamentals of fuse design are given, as well as the reason for possible indiscriminate operation between fuses of different types.The need to break away from some time-honoured practices is shown, with particular reference to plugs and tumbler switches; solutions based on theoretical and practical considerations are presented. Some parts of the paper may appear elementary, but their inclusion is justified by the many accessories on the market and installed which reveal a lack of elementary engineering knowledge in those responsible for their design, production and installation.It is hoped that the paper will stimulate progress in the design of the accessories under consideration and raise the standard of this branch of the electrical industry to its proper level. But progress will be delayed if electrical contractors persist in considering only the first cost and ignoring the costs of installation and maintenance.The author strongly supports and recommends British Standard Specifications, but feels that they should be confined to setting standards of performance, with interchangeability only where required, and that constructional details and dimensions thereon should be omitted so as to give maximum freedom for development and, therefore, progress in design.