Transparency is a communicative process whose aim is to provide citizens with information that will promote their participation in public affairs. However, its application is often reduced to a legally stipulated administrative act. In contrast, this article sets out the principles, attributes and evidence of transparency from a communication perspective, taking into consideration that transparency is treated as a process through which recipients obtain, understand and use information. This study focuses on the transparency of local town councils, although most of the concepts could be applied at other levels of public administration. To establish this framework, the legislation and application of transparency in three countries (Spain, Ecuador and Colombia) was studied using the Infoparticipa method designed with a communication approach in mind. A comparative study was then carried out using methods designed in other disciplines. Through this approach, the benefits of transparency were categorized to define six principles—disclosure, strengthening, visibility, comprehensibility, dissemination and humanism—and eight attributes of transparent information: veracity, timeliness, accessibility, usability, intelligibility, universality, pluralism and plurality. For each attribute, the evidence of its application was determined. This framework clarifies the perspective of transparency for participation from a communication approach.