A software product line oriented approach to developing systems has an impact on the development process as a whole. Although the basic idea of product lines is simple, systematic implementation of the approach is a challenging task. In fact, today's software product lines have such complex variability that their handling must be supported by tools, otherwise a systematic approach would not be possible. The same holds for requirements management of product lines. On the basis of specific industrial scenarios the paper derives important requirements that have to be observed if requirements management tools are to be usefully applied to product lines. Current requirements management tools are evaluated on the basis of these requirements in their daily industrial use. The presented requirements can indicate the future direction of tool development and method research.

Industrial requirements specifications suffer from consistency problems, particularly in multi-angular or temporal relationships between different specification results. Current consistency management tools generate too many repairs, lack support for temporal relationships, and are poorly integrated into development processes. In this paper we evaluate our consistency management method on how it improves quality of industrial specifications: we formalize (temporal) consistency rules and generate a few domain-specific repairs for inconsistencies. We demonstrate our method using an example specification. Since the effort for formalization is tunable to specific applications and our prototype shows satisfactory performance, we are confident that our contributions scale to an industrial setting.

ISO/IEC 15504 is an emerging international standard on software process assessment. It defines a number of software engineering processes and a scale for measuring their capability. One of the defined processes is software requirements analysis (SRA). A basic premise of the measurement scale is that higher process capability is associated with better project performance (i.e., predictive validity). The paper describes an empirical study that evaluates the predictive validity of SRA process capability. Assessments using ISO/IEC 15504 were conducted on 56 projects world-wide over a period of two years. Performance measures on each project were also collected using questionnaires, such as the ability to meet budget commitments and staff productivity. The results provide strong evidence of predictive validity for the SRA process capability measure used in ISO/IEC 15504, but only for organizations with more than 50 IT staff. Specifically, a strong relationship was found between the implementation of requirements analysis practices as defined in ISO/IEC 15504 and the productivity of software projects. For smaller organizations, evidence of predictive validity was rather weak. This can be interpreted in a number of different ways: that the measure of capability is not suitable for small organizations or that the SRA process capability has less effect on project performance for small organizations.

The effectiveness of software engineering technologies depends very much on the situation in which they are applied. In order to further improve software development practices one needs to explicitly describe and utilise knowledge about application domains of software engineering technologies. The paper suggests a modelling formalism for supporting systematic reuse of software engineering technologies during planning of software projects and improvement programs.