Requirements engineering challenges and practices in large-scale agile system development

Context: Agile methods have become mainstream even in large-scale systems engineering companies that need to accommodate different development cycles of hardware and software. For such companies, requirements engineering is an essential activity that involves upfront and detailed analysis which can be at odds with agile development methods. Objective: This paper presents a multiple case study with seven large-scale systems companies, reporting their challenges, together with best practices from industry. We also analyze literature about two popular large-scale agile frameworks, SAFe® and LeSS, to derive potential solutions for the challenges. Methods: Our results are based on 20 qualitative interviews, five focus groups, and eight cross-company workshops which we used to both collect and validate our results. Results: We found 24 challenges which we grouped in six themes, then mapped to solutions from SAFe®, LeSS, and our companies, when available. Conclusion: In this way, we contribute a comprehensive overview of RE challenges in relation to large-scale agile system development, evaluate the degree to which they have been addressed, and outline research gaps. We expect these results to be useful for practitioners who are responsible for designing processes, methods, or tools for large scale agile development as well as guidance for researchers.