A number of research challenges in the area of program comprehension are presented. The expressiveness and effectiveness of program comprehension are discussed, and research directions are organized along these two axes. Both fundament research issues are raised along with new applications for program comprehension methods. The work advocates the investigation of better measures, further empirical studies, and controlled experiments to assess the effectiveness of program comprehension techniques 1.

Standards demand that assurance cases support safety critical developments. It is widely acknowledged, however, that the current practice of post-hoc assurance—that the product is built and only then argued for safety—leads to many engineering process deficiencies, extra expense, and poorer products. This paper shows how the Problem Oriented Software Engineering framework supports the concurrent design of a safe product and its safety case, by which these deficiencies can be addressed. The basis of the paper is a real development, undertaken by the second author of this paper, of safety-related subsystems of systems flying in real aircraft. The case study retains all essential detail and complexity.