While therapeutic endovascular occlusions date from as early as 1904, it is in the last 20 years that therapeutic neutroradiology has come into its own. Progress has been made in four directions. (1) Embolization has developed from the original technique involving arteriotomy, through percutaneous methods, to present-day superselective catheterization. Concurrently, the materials used have been improved: from nonmalleable muscle and Silastic balls, to malleable Spongel and dura mater, and most recently to polymerizable fluid plastic substances. The possibility of obstructing very narrow vessels extends the range of indications of embolization. (2) Balloon catheters have been developed, first with nondetachable balloons (1971), more recently with detachable ones (1974). (3) Other techniques may be used to produce a therapeutic thrombosis, e.g., endovascular electrocoagulation and thermocoagulation. (4) Foreign bodies may be extracted safely by catheterization. Further development of techniques should ensure a growing importance for therapeutic neuroradiology in the future.