Today the threat of terrorism is becoming more and more serious. Terrorism is considered the greatest threat against the safety of the world, and especially the USA, today. The extent of the terrorism has increased significantly over the last couple of years, since the terrorist attacks against the US on the 11th of September 2001. After these attacks former president of the US, George Bush declared a war against terrorism. There are various opinions about what can be defined as terrorism. Because there are so many situations that can be defined as terrorism, it is be very difficult to find an exact definition. Many countries have different definitions, and the definitions have also changed over the years. Not even the UN has managed to agree about one common definition. In short we can say that terrorism is some sort of attack at civilians to achieve a political goal. Terrorism has existed for many centuries, but in the last couple of years the attacks have become more extensive and the devastations has become greater. In the future scientists expect that the terrorists will carry out actions with weapons of mass destruction such as chemical, radiological and biological weapons. The war on terrorism is a global campaign led by the USA. The goal is to fight international groups that are considered to be terroristic. They especially focus on radical Islamic terror groups, such as the Al-Qaida. Today the war on terrorism goes on in countries such as Afghanistan, the Philippines, Indonesia, Iraq, and Israel. Many human rights organizations have criticized the war on terrorism because they think it in many cases can lead to violations of the human rights. Around the globe there are various terrorist organizations, all with different goals and reasons for their terrorist-activities. The most known group today might be the Al – Qaida which origins form Afghanistan, but has become an international organization. The Al-Qaida became known after the terrorist actions on the 11th of September 2001 when 4 airplanes were hijacked. Two of them were flown into the two main buildings of the World Trade centre in New York. One airplane was crashed into the Pentagon, and the last airplane crash-landed in a field in Pennsylvania. After these attacks the USA decided to attack Afghanistan. The leader of Al-Qaida is Osama Bin Laden who has been hiding from the US troops ever since the war started. The reasons for Al-Qaida’s actions are based on the Islamic “Sharia” – laws. They want to fight the states they consider a threat against Islam, and especially the USA and Israel. The Al-Qaida leaders encourage all Muslims to kill American citizens, both military and civilians. We can separate the terrorist actions into two main groups; local and international terrorism. Local terrorism consists of actions such as suicide missions, car bombings and so on. International terrorism is actions where the citizens and/or territory of several countries are affected. There are many situations that can lead to the use of terrorism. Terrorism can occur in both poor as well as wealthy countries, and in both democracies and states under different kinds of dictatorship. However, terrorism is most likely to occur in countries that are characterized by poverty and oppression. People in poor countries might feel like they are subjected to an unfair distribution of the world’s wealth. Poverty is claimed to be an underlying part of all the causes of terrorism. Terrorism is a global issue that has to be fought globally. Organizations like the UN, NATO and the EU have the war against international terrorism as their highest priority. The UN is currently working on a convention that can be an important part of handling terrorism. They have also established a strategy on how we can fight the terrorism. But we still have a long way to go, and the world might never be completely terror-free. However, if we work on preventing planned terrorist-actions and focus on improving the circumstances that lead to terrorism, the amount of terrorism could be decreased significantly.