In the streaming era, the very thing that defines it is what threatens to impede access to important media history and cultural heritage. Streaming’s barriers to entry and its interim content catalogs challenge the actual collection and preservation of it for research and teaching purposes. If researchers and libraries do not work together to document and preserve these, we will keep losing important sources and data. From a collection perspective, we argue that streaming services consist of their catalog, metadata, and graphical user interfaces. First, we map the large-scale legal deposit collection of streaming at a national library as well as a media researcher’s small-scale targeted collection. Second, we compare the resulting collections of web sites and graphical user interfaces in order to discuss methodological challenges. The findings of this comparative analysis indicate the existing deficiencies in both collections and suggest potential improvements in the collection and preservation of streaming services.