Public organizations have interacted with citizens through increasingly sophisticated internet-enabled technology. Participatory platforms emerged from Web 2.0 technologies in the mid-2000s as a governance mechanism to engage citizens in the process of effecting social change. Although the potential of platforms is recognized, its successful implementation has faced challenges. To begin to get a handle on how to best design and manage participatory platforms, we conducted an exploratory participatory action research study grounded in two events – The Policy Challenge and NSF Workshop on Participatory Platforms with a Public Intent. Both events communed practitioners, scholars, and citizen participants with diverse experience and expertise conducting and researching platforms. The insights expressed through the events and follow-up interviews and online survey informed our development of a participatory platform lifecycle and design framework to assist designing successful participatory platforms.