The term semi-professional can be used to denote occupational groups that do not have emergency response as their primary profession but who get additional responsibilities within rescue and response, e.g. by performing a first response or assisting the professional emergency services. In this study, four different groups of possible semi-professional resources are analyzed and compared. Similarities and differences between the four groups are discussed. Factors, important for the successful implementation of a cross-sector collaboration of this kind, are highlighted. The preliminary results show that all four groups have the potential to act as semi-professional resources within emergency response. Interestingly, the basic requirements are the same for all groups, despite different prerequisites.