Abstract: This paper examines the problem of achieving efficient inter-organizational collaboration during emergency response. The authors interviewed 11 representatives from Norwegian emergency agencies and supporting organizations about a hypothetical scenario involving a large-scale chemical incident. The interviews resulted in the identification and categorization of more than 45 actors that would be involved in the response effort, clarification of the individual capabilities and knowledge those actors would possess, and descriptions of how they would interact and communicate with each other. The results illustrate the complexity and necessity of achieving inter-organizational collaboration by showing how capabilities and knowledge are distributed and communicated across different actors, and suggest that such communications are mainly verbal. Based on this, the paper discusses challenges and opportunities for improving inter-organizational collaboration in the future.