Introduction On April 15, 2013, two bombs went off almost simultaneously on Boylston Street during the 117 th annual Boston Marathon at 2.49 pm EDT (Gessen, 2015). Three people were killed and over 260 others were wounded, with some of the victims losing their limbs. The security agencies had conducted a thorough screening of the area as a standard procedure given the population that was expected to attend this popular event on Patriots’ Day in Boston. Their searches did not reveal any threat of bomb attacks. The incident led to a major manhunt for the suspects and on April 18, the Federal Bureau of Investigation was able to identify the suspects who were involved in this attack. It was noted that the attack was carried out by two Islamic brothers, Tamerlan Tsarnaev and Dzhokhar Tsarnaev, who felt that the United States actions in Iraq was hurting the Islamic communities in these regions. A section of the local and international community has blamed this attack on intelligence sharing failure. Although it was almost impossible for the security agencies to know about this attack, one of the suspects was already under FBI and CIA records as one of those who had joined radical Islamic groups. In this paper, the researcher seeks to determine if the Boston Marathon Bombing was as a result of intelligence sharing failure among the security agencies. Purpose of the study The United States is one of the countries that are often targeted by various terror groups, especially the Islamic terrorists in the Middle East and other parts of the world, because of its stance on leadership in the region. The security agencies in the country have a tough responsibility of gathering intelligence and acting upon it to ensure that terror threats are thwarted before an attack can materialize. The Federal Bureau of Investigation and Central Intelligence Agency have the task of gathering intelligence and sharing it with other local authorities with the aim of protecting American citizens and property from potential attack. On April 15, 2013, three Americans lost their lives and over 260 others were seriously wounded on a day that Boston was celebrating Patriots’ Day (Sherman & Wedge, 2015). It meant that in one way or the other, the security agencies failed in their mandate to protect American citizens and their property at such an important event. The purpose of the study is to identify the failure on the part of these security agencies to ensure that such events do not occur again in future. By identifying the weakness, the security agencies would be able to avoid them during similar future events. Methodology Boston Marathon Bombing is an issue of public concern, and various media stations reported the matter at various stages after the attack. Cases of misreporting and mistaken identities were common as the entire society worked hard to identify the suspects and to ensure that they are brought to justice. As such, it was important to find an appropriate method of collecting information in this research in a way that would yield the most accurate data possible. Determining whether this bombing was made possible because of intelligence sharing failure requires a valid method of collecting accurate data from reliable sourc