Abstract: Technology undeniably plays an important role in supporting crisis managers to respond to crisis. However, when improperly designed or used, technology can be ineffective or even be detrimental to the crisis response. Therefore, in this paper we bring together insights from the scientific literature and identify 5 principles for the design and use of technology to aid crisis managers effectively. These principles might seem trivial but there are several examples of technology used in practice that show the opposite. To illustrate this, we use as a case study the Dutch nation-wide crisis management system LCMS which is used in the Netherlands by all safety regions and other public organizations to maintain and share a common operational picture supporting large-scale crisis management collaboration. We explain why crisis evaluations and research time and again show that LCMS has failed to add value for crisis managers during crisis by using the identified principles.