PurposeThis article aims to advance a new theoretical perspective on the basis of prosumption theory, namely, that online review platforms can be conceptualized as prosumer communities (and online reviews as prosumer-generated content). This perspective meshes with message tuning research to suggest specific mechanisms through which peer-to-peer prosumption takes place in online review communities. Overall, this article enriches and deepens theoretical understanding of prosumption behavior in the product review context and offers practical advice for inducing high-value, prosumer-generated content in online communities.Design/methodology/approachExploratory observations of current practices across a wide spectrum of review platforms were conducted. The observed platforms include independent review sites (e.g. Yelp) and review sites affiliated with e-tailers (e.g. Amazon), general review sites (e.g. Viewpoints) and product-specific review sites (e.g. Healthgrades), large-scale review sites (e.g. TripAdvisor) and review sites of a smaller scale (e.g. Judy’s Book) and review sites based in different geographic regions, including Australia (e.g. Productreview.com.au), China (e.g. Taobao), Europe (e.g. Reevoo), India (e.g. Zomato) and North America (e.g. Foursquare).FindingsTheoretical analysis suggests that high-quality review content is the result of collaborative prosumption characterized by three distinct value-adding processes: history-based message tuning, audience-based message tuning and norm-based message tuning. In-depth observations reveal that today’s review platforms are leveraging these value-adding processes to varying degrees. The overwhelming diversity of the observed platform features points to the need for more research on platform design and management.Research limitations/implicationsThis research identifies three distinct dimensions of review quality – novelty, relevancy and congruency – that can be systematically managed through platform design. The exploratory nature of this research necessitates follow-up work to further investigate how high-quality review content emerges in the historical, interpersonal and cultural contexts of online prosumer communities.Practical implicationsThe prosumption-inducing mechanisms identified in this research have major consumer welfare and strategy implications. First, they may lead to novel, relevant and congruent consumer reviews. Second, they may enhance the value of brand communities (which rely heavily on collaborative prosumption).Originality/valueThis research addresses two intriguing questions pertinent to marketing theory and practice in the digital era. First, how do high-quality reviews emerge on product review platforms (which consist of ordinary consumers)? Second, what constitutes high-quality review content and how can platform managers facilitate the collaborative creation of high-quality review content by ordinary consumers?