Volunteered geographic information (VGI) has been seen as useful information in times of disasters. Several authors have shown that VGI is useful for coping with preparedness and response phases of disaster management. However, because it is still a young technology, the use of VGI remains uncertain, due to its lack of strong reliability and validity. It is our assumption that to improve reliability and validity the promotion of citizen engagement (CE) is needed. CE is not new topic, but in the digital humanitarian context, it involves important factors that are not yet considered by disaster managers, such as communication processes, motivation of volunteers, different media for production of information, etc. To fill this gap, we identified a set of preliminary factors which should be considered to promote the involvement of volunteers in disaster management. These factors were derived from critical review of CE literature and from an analysis of lessons learned from an experiment on interaction with citizens carried out in context of the EU-project “DRIVER – Driving Innovation in Crisis Management for European Resilience”.