Lower gastrointestinal bleeding (LGIB) is associated with high morbidity and mortality. Embolization is currently proposed as the first step in the treatment of acute, life-threatening LGIB, when endoscopic approach is not possible or is unsuccessful. Like most procedures performed in emergency setting, time represents a significant factor influencing outcome. Modern tools permit identifying and reaching the bleeding site faster than two-dimensional angiography. Non-selective cone-beam CT arteriography can identify a damaged vessel. Moreover, sophisticated software able to detect the vessel may facilitate direct placement of a microcatheter into the culprit vessel without the need for sequential angiography. A further important aspect is the use of an appropriate technique of embolization and a safe and effective embolic agent. Current evidence shows the use of detachable coils (with or without a triaxial system) and liquid embolics has proven advantages compared with other embolic agents. The present article analyses these modern tools, making embolization of acute LGIB safer and more effective.