Specifies requirements and gives guidelines for the exposure and removal of weaknesses in hardware and software items for the purpose of reliability growth. Applies when the product specification calls for a reliability growth programme of equipment (electronic, electromechanical and mechanical hardware as well as software) or when it is known that the design is unlikely to meet the requirements without improvement. The main changes with respect to the previous edition are listed below. A subclause on planning reliability growth in the design phase has been added. A subclause on management aspects covering both reliability growth in design and the test phase has been added. A clause on reliability growth in the field has been added.