Change is unavoidable in software development. During the entire lifecycle of a product, from concept to retirement, the environment changes; the needs of customers or the market change and grow, and with them the requirements on the system being developed. Under these conditions, it is crucial to have strong change control in order to be able to manage change in an orderly fashion. Unmanaged change may lead to fault-prone software, thereby increasing test, support and maintenance costs. Impact analysis is the activity of analysing a change and assessing the consequences it may have, including necessary modifications to development artefacts. Thus, it serves as a very important change control tool. Furthermore, as the consequences may include aspects of time, resources, market and technology, impact analysis has the potential to be a valuable product and project management tool. To this date, impact analysis research has mainly been conducted in the software maintenance field. However, as impact analysis clearly has a wide field of application, it is relevant to study it in other contexts as well. This thesis looks at impact analysis from a requirements engineering perspective, with particular focus on organisational aspects related to different roles and organisational levels. The results show that impact analysis indeed has a diverse nature with respect to these aspects. Furthermore, the thesis includes the proposal and evaluation of a semi-automatic method for performing impact analysis. Finally, it provides a thorough evaluation of a technique for reconstructing missing data in surveys.

Avhandlingen handlar om påverkansanalys av programvaruändringar under utvecklingscykeln. Påverkansanalys diskuteras från ett organisatoriskt perspektiv med fokus på kravhantering. Detta skiljer sig från majoriteten av existerande forskning, där man typiskt har ett tekniskt perspektiv samt fokuserar på programvaruunderhåll. Nyckelord: påverkansanalys, roller, organisatoriska nivåer, kravhantering