Online interactions between unknown parties are increasingly common. This is particularly exemplary in Virtual Organizations (VO). A VO is understood as a permanent or temporary alliance of enterprises that share their resources and skills to achieve specific business goals (collaboration opportunity). In this sense, the lack of trust between partners is seen as an hindrance to the VO’s operation. Thus, reputation systems can be applied to trust establishment and management among VO’s partners. Therefore, this paper presents a taxonomy to classify and compare trust and reputation systems applied to VO’s context. The taxonomy is based on literature studies regarding characteristics observed through a systematic review process. In order to evaluate the proposed taxonomy, it was applied to trust and reputation systems obtained through a systematic review process. Finally, according the presented results, it is possible to note a gap concerning reputation systems applied to the context of VO and Cloud Computing integration.