Embolization has been performed in many European countries and in North America for over 20 years and is now beginning to gain accep tance in other countries. At first, experience with these techniques was shared in the form of individual case reports; today some centers have treated enough patients to be able to transform this anecdotal material into more concrete data. For the last 10 of these 20 years, the two of us have been deeply involved, encouraged, and stimulated by the interest created by the few pioneers in endovascular techniques. In 1978, when we first met, our discussion on embolization could have been summarized as disagreement. It soon became obvious that these differences were primarily related to our different individual back grounds. One of us having a strong orientation toward anatomy, and the other toward technique. We realized that these apparently opposing approaches complement each other and decided to combine them to our mutual benefit. This collaboration has matured into the search for improvements in patient care and for the safest, most reliable, and most responsible manner of treatment.
