The collapse of project Taurus, a @$500 million IT venture commissioned by the London Stock Exchange, ranks as one of the major fiascos of business history. This paper examines key events in the design and construction of Taurus with reference escalation theory. Escalation theory concerns the tendency of organizations to become trapped in failing projects like Taurus and to persist with them irrationally. Two features of escalation and subsequent failure are highlighted. First, the destructive progression whereby one sub optimal decision forces another. Second, a process of means/ends reversal whereby a pre-occupation with delivering Taurus obscures the reality that Taurus is no longer worth delivering.