This paper proposes a six-step maturity ladder for inter-organizational collaborative capability in crisis management and response operations. The paper argues that collaborative crisis management and response can be seen as a case of complex adaptive systems, where awareness of the organizational context of crisis response, technical interoperability, and individual relations are drivers that enable rapid and successful mobilization of crisis response. The maturity ladder provides a link between the capabilities necessary for collaboration possessed by individual crisis response entities and the overall system maturity in terms of collaborative crisis management capability. It can inter alia be used as a basis for a discussion when inter-organizational exercises are appropriate and when focus must remain on the development of the capabilities of individual crisis response entities.