ISKME created OER Commons, publicly launched in February 2007, to provide support for and build a knowledge base around the use and reuse of open educational resources (OER). As a network for teaching and learning materials, the web site offers engagement with resources in the form of social bookmarking, tagging, rating, and reviewing. OER Commons has forged alliances with over 120 major content partners to provide a single point of access through which educators and learners can search across collections to access over 30,000 items, find and provide descriptive information about each resource, and retrieve the ones they need. By being "open," these resources are publicly available for all to use, and principally through Creative Commons licensing, many thousands are legally available for repurposing, modifying and improving.