The authors compared guided Internet-delivered self-help with one session of live-exposure treatment in a sample of spider-phobic patients. A total of 30 patients were included following screening on the Internet and a structured clinical interview. The Internet treatment consisted of five weekly text modules, which were presented on a web page, a video in which exposure was modelled, and support provided via Internet. The live-exposure treatment was delivered in a 3-hr session following a brief orientation session. The main outcome measure was the behavioural approach test (BAT), and as secondary measures the authors used questionnaires measuring anxiety symptoms and depression. Results showed that the groups did not differ at posttreatment or follow-up, with the exception of the proportion showing clinically significant change on the BAT. At posttreatment 46.2% of the Internet group and 85.7% in the live-exposure group achieved this change. At follow-up the corresponding figures were 66.7% for the Internet group and 72.7% for the live treatment. Within-group effect sizes for the spider phobia questionnaire were large (d = 1.84 and 2.58 for the Internet and live-exposure groups, respectively, at posttreatment). The authors conclude that guided Internet-delivered exposure treatment is a promising new approach in the treatment of spider phobia.