Using the Radiance Platform you can segregate your audience by Segments or Lists and then market to a curated audience. Segments allow you to narrow down to a subset of your opted in audience based on a set of criteria. Lists are sets of opted in subscribers that are enumerated by ID. You also have the option of uploading a specific group of opted in users instead of creating them as a segment or list in the console. Note: There may be 1-2 hour delay before new opt-ins are reflected in segments.