Context: Soft skills (e.g., communication skills, empathy, team skills) impact software project success. Objective: We aim to understand (1) how soft skills are defined and perceived in the software industry, (2) what soft skills are required in software development roles, (3) how soft skills are trained, and (4) how soft skills are assessed in the software industry. Method: We conducted 18 semi-structured interviews with software professionals in different roles. We manually analyzed transcripts following a general inductive approach. Results: There is ambiguity in soft skills definition, but agreement on their importance. Most critical soft skills were communication, leadership, and teamwork skills, but we also identified less frequently discussed skills: resilience and self-awareness. Further, we find that soft skills are not systematically assessed, likely due to difficulties in their assessment. A theme emerged on the importance of ongoing soft skills training as well as tailoring training to software professionals’ needs. Conclusions: Our research supports past research on the importance of soft skills in software engineering and suggests that further emphasis is needed on soft skills assessment and training. We discuss implications for software professionals, those in leadership roles, and companies.