The phenomenon of inter-organizational cooperation in networks is becoming increasingly important, and as such there are numerous companies which participate in various networks. This is due to the advantages offered by participation in such networks, e. g. access to the resources of partners, the opportunity to learn from partners, reduction of risk, etc. Even the negative aspects of functioning within the network do nothing to reduce the attractiveness of this concept. It should be noted, however, that any inter-organizational cooperation is combined with the likelihood that certain negative phenomena may arise, i.e. pathologies which reduce the attractiveness of this type of activity. Some of these pathologies are similar to those occurring in any organization, while the others are a specific feature of network organizations. The aim of the paper is to analyse the pathologies most frequently observed in inter-organizational networks. In contrast to pathologies resulting from a specific network structure (hereinafter referred to as structural pathologies) we have labelled such phenomena simple pathologies. Our analysis begins with a presentation of the importance of network organizations in contemporary business. We then present the major pathologies in networks and the varieties thereof. Subsequently, a comparison is made between pathologies in the organization vs. the pathologies in the networks. Finally, we have described the ways to avoid pathologies in networks, as well as summarised the potential solutions. The paper utilises the publications available in the literature, as well as the authors' experience in creating network organizations. Although it is impossible to identify a universal solution to the issue of pathologies in the networks (because their sources are complex and systemic in nature), knowledge of such phenomena can reduce the risk of their re-occurrence. (C) 2014 Elsevier B.V.