Using the domain of crisis management, Christian Reuter explores challenges and opportunities for technology design in emergent environments. He therefore empirically analyzes collaborative work in inter-organizational crisis - such as the police, fire departments, energy network operators and citizens - in order to identify collaboration practices that reveal work infrastructure limitations. He also designs, implements and evaluates novel concepts and ICT artifacts towards the support of emergent collaboration. Besides the discovery of potential organizational effects on the ability to deal with emergence he presents methodological implications for technology design. Contents Towards a Systematization of Social Software Use in Crisis Situations Emergent and Improvisational Collaboration Practices in Crisis Inter-Organizational Social Network for Emergency Management Geospatial Mashup for Information and Expertise Sharing in Situation Assessment Mobile Applications for Ad Hoc Participation in Mobile Collaboration and Articulation Work in Mobile Reporting Target Groups Researchers and students in the fields of information systems, human computer interaction, computer support collaborative work and crisis management Practitioners in these areas The Author Dr. Christian Reuter studied in Siegen and Dijon. After working as a consultant he joined the Institute of Information Systems at the University of Siegen.