When building an eParticipation environment, many questions arise. Who will the participants be? What are the outcomes? How will citizens interact? How will they be selected? All these questions will influence the specification of an eParticipation environment. In order to create an effective eParticipation environment, the designer pays attention to all these characteristics, which can be tricky, especially when selecting ICTs to support the eParticipation process. This paper suggests the use of an ontological approach when specifying these eParticipation environments, in order to reduce the designer’s cognitive efforts when designing effective eParticipation environments.