A significant share of architectural energy is spent on reducing or avoiding lock-in. That's a rather noble objective: architecture is meant to give us options and lock-in does the opposite. However, lock-in isn't a simple true-or-false matter: avoiding being locked into one aspect often locks you into another. Also, popular notions, such as open source automagically eliminating lock-in, turn out to be not entirely true. Time to have a closer look at lock-in, so you don't get locked up into avoiding it!