ArtBabble (http://www.artbabble.org) and ARTtube (http://www.arttube.nl) are similar, collaborative museum websites about art and design, initiated by two museums across the globe. Both have launched dedicated online platforms for art-related video; both encourage stronger interrelations between diverse museums’ content and better reach of targeted audiences. Beyond these similarities, both websites and their administration function in different ways. This paper compares both projects as interesting case studies for online museum collaboration. The recent redesign of both platforms reflects their diverse strategies for managing growth and sustainability.