Two suicide bombers detonated explosives in Bourj el-Barajneh, Beirut, killing 43 people and injuring over 200 others.

On 12 November 2015, two suicide bombers detonated explosives in Bourj el-Barajneh, a southern suburb of Beirut, Lebanon, that is inhabited mostly by Shia Muslims. Reports of the number of fatalities concluded that 43 people died directly from the detonation. Islamic State of Iraq and the Levant (ISIL) claimed responsibility for the attacks.The bombings were the worst terrorist attack in Beirut since the end of the Lebanese Civil War. They came twelve days after the bombing of a Russian airliner over the Sinai Peninsula that killed 224 people and a day before attacks in Paris that killed 137. ISIL claimed responsibility for these attacks as well.

Around 48 hours after the attack, Internal Security Forces arrested eleven people, mostly Syrians, over the attack. It later announced the arrest of two other Syrian and Lebanese suspects. They were arrested in a Palestinian refugee camp located in Burj al-Barajneh and a flat in the capital's eastern district of Achrafieh, which had allegedly been used to prepare the explosive belts. The initial plan was apparently to send five suicide bombers to a hospital in the neighbourhood, but heavy security forced them to change the target to a densely populated area.

A suicide attack is any violent attack, usually entailing the attacker detonating an explosive where the attacker has accepted their own death as a direct result of the attacking method used. Suicide attacks have occurred throughout history, often as part of a military campaign (as with the Japanese kamikaze pilots of 1944–1945 during World War II), and more recently as part of terrorist campaigns (such as the September 11 attacks in 2001).

While few, if any, successful suicide attacks took place anywhere in the world from the end of World War II until 1980, between 1981 and September 2015 a total of 4,814 suicide attacks occurred in over 40 countries, killing over 45,000 people. During this time the global rate of such attacks grew from an average of three a year in the 1980s to about one a month in the 1990s to almost one a week from 2001 to 2003 to approximately one a day from 2003 to 2015.Suicide attacks tend to be more deadly and destructive than other terror attacks because they give their perpetrators the ability to conceal weapons, make last-minute adjustments, and they do not require remote or delayed detonation, escape plans or rescue teams. They constituted only 4% of all terrorist attacks around the world over one period (between 1981 and 2006), but caused 32% of all terrorism-related deaths (14,599). Ninety percent of those attacks occurred in Afghanistan, Iraq, Israel, the Palestinian territories, Pakistan, and Sri Lanka. Overall, as of mid-2015, about three-quarters of all suicide attacks occurred in just three countries: Afghanistan, Pakistan, and Iraq.Suicide attacks have been described (by W. Hutchinson) as a weapon of psychological warfare to instill fear in the target population, a strategy to eliminate or at least drastically diminish areas where the public feels safe and the "fabric of trust that holds societies together", as well as to demonstrate the lengths to which perpetrators will go to achieve their goals.Suicide attackers may have various motivations. Kamikaze pilots acted under military orders, while other attacks have been perpetrated for religious or nationalist purposes. Before 2003, most attacks targeted forces occupying the attackers' homeland, according to analyst Robert Pape. Anthropologist Scott Atran states that since 2004 the ideology of Islamist martyrdom has motivated the overwhelming majority of bombers.