In spring 2007 Estonia was subjected to an Internet blockade lasting several weeks. During this time the net did not work normally. It became hard to reach authorities and the mass media via the Internet, for a brief period Internet banks had to interrupt their business, and for several extended periods it was hard to communicate with the rest of the world via the Internet. How would Sweden cope with a similar situation? This is one of the questions we had in mind when we drew up this report, which is divided into two sections. The first part charts the events in Estonia, including the special circumstances that led to the country being subjected to extensive Internet attacks. In the second part we look at how Sweden is equipped for similar events, i.e. what it would do if the country were subjected to more or less organised attacks.