The idea of thrombolysis for acute ischemic stroke dates back to the 1950s. Many different drugs, dosages, routes of administration, and times to treatment have been investigated through the 1980s. This experience led to the recent large randomized trials of intravenous thrombolysis completed in the 1990s, the decade of the brain. Three of the trials used streptokinase, and four trials used recombinant tissue plasminogen activator (rt-PA). In this review, we examine these seven randomized intravenous acute ischemic stroke treatment trials, summarize their results, and draw lessons that might be useful for patient care and in future trials.