Guiding over 30 million registered users to the right professional contact is what searching at LinkedIn is all about. According to LinkedIn, literally billions of searches are analyzed. Member search is implemented using Lucene, and filtered according to a searching user's network. According to Forbes LinkedIn offers'laser-like targeting'. In November 2008, new search capabilities were released, including:

• Suggested (auto-complete) search of contacts
• Changing the view of search results
• Refining search results according to multiple criteria, including your social graph.
• Take actions directly from the search results, such as sending email
• Saving searches
• Notification when new connections meet search criteria

LinkedIn has also contributed some of their search efforts back to the open source community, with project such as:

• Zoie, a real-time search and indexing system.
• Kamikaze, a compression scheme to iterate over sets in a compressed form.
• Bobo, a high performance faceted/parametric search implementation.