The GRF EXORD generally establishes the GRF as a set, or “menu,” of forces from the military services—each of which possesses unique capabilities—that the Secretary of Defense can deploy rapidly anywhere in the world. According to Joint Staff officials, deployment is for a duration that can range from a few weeks to several months. The GRF EXORD was first issued in 2007 and, according to DOD officials, has been revised several times to modify the number or types of assigned units. The current version, which was issued in 2015, continues to identify two uses for the GRF, described as follows: One is to enhance DOD’s ability to respond quickly to a range of worldwide contingencies. In this scenario, the GRF would generally be used as a tailorable joint force. For example, in the event of a humanitarian crisis such as an earthquake, GRF units possessing the capabilities needed to meet the crisis can be combined into a joint force and rapidly deployed to the affected area. In this scenario, the GRF units selected would act together as a joint force under the GRF- supplied Joint Task Force headquarters or a preexisting one. The other identified use of the GRF is to augment the capabilities of geographic combatant commands in light of unexpected challenges. In this scenario, GRF units would generally be deployed as individual units or in groups. For example, a combatant command may on occasion require additional intelligence, surveillance, and reconnaissance capability, and accordingly a GRF unit possessing that requisite capability can be taken from the GRF and temporarily allocated to the combatant command for a certain period of time. Although the GRF EXORD identifies these two intended uses, the document does not prioritize one use over the other. To meet the range of capabilities delineated in the GRF EXORD, the services nominate and assign units to the GRF on a rotating basis for a certain period of time. Each nominated and assigned unit possesses a specific capability outlined in the GRF EXORD. These specific capabilities correspond to the operational requirements of eight global mission scenarios listed in the GRF EXORD. For example, the GRF includes a Marine Expeditionary Unit and an Airborne Brigade Combat Team because of the unique capabilities of those units. According to DOD officials, once a force is assigned to the GRF, it is on alert status for a period of typically 6 to 9 months, with a potential to be deployed. Accordingly, services rotate units onto and off of the GRF in order to maintain a high state of readiness, which, in turn, allows them to meet the rapid response timeframes required by the GRF EXORD. To gain access to units assigned to the GRF, according to Joint Staff officials, combatant commanders submit an emergent request for forces to the Joint Staff. Generally as part of the global force management process, when a combatant command identifies an emergent requirement for a force that cannot be met using units already assigned or allocated to the combatant command, the combatant command then submits a request for forces. If the Joint Staff, joint force providers, and military services determine that a GRF-assigned unit is the most appropriate solution for the combatant command’s requirement, the Joint Staff will recommend it as the sourcing solution to the Secretary of Defense. Once approved, the GRF-assigned unit will be allocated to the combatant commander. According to an official from the Joint Staff office responsible for managing the GRF across DOD, since 2010 DOD has used the GRF 35 times in support of worldwide contingencies—with 32 of those uses involving individual GRF units being deployed in support of or to augment combatant commander needs. However, according to Joint Staff officials overseeing the management of the GRF, DOD has not assessed the extent to which it assumes risk associated with the potential unavailability of GRF units for a short-notice deployment as a joint force in response to a contingency, given the predominant use of the GRF as a resource for combatant commands to obtain individual units. According to an official from the Joint Staff, deployment of select GRF units as part of a joint task force has occurred three times: once to Haiti in support of an earthquake humanitarian response, and twice to Afghanistan in July 2010 and June 2011 in support of Operation Enduring Freedom. According to these officials, GRF capabilities in support of Haiti included command and control, security, and transportation and distribution of humanitarian supplies. GRF units in support of Operation Enduring Freedom provided force protection to coalition forces as well as train, advise, and assist capabilities. The predominant use—32 of 35 deployments—of individual GRF units to augment a combatant commander’s needs has, in turn, diminished the set of units available for mission scenarios related to the GRF’s use as a tailorable joint force, and accordingly the capabilities available for inclusion under a GRF joint task force. For example, Joint Staff officials stated that DOD deployed a ballistic missile defense unit designated for the GRF to a geographic combatant commander’s area of responsibility to augment that combatant command’s missile defense capabilities. According to Joint Staff officials, the deployment of individual GRF- assigned units is intended to be a temporary solution for a specified period of time. According to these officials, the ballistic missile defense unit’s deployment was extended beyond its original timeframe and it was not replaced on the GRF menu of forces with another such unit because there are not enough of these particular types of units to meet the requirements across the combatant commands. Therefore, during the ballistic missile defense unit’s deployment, the particular capability that unit supplied to the GRF was not available as part of a tailorable joint force to respond quickly to a potential worldwide contingency—the other broad intended use of the GRF. Given that DOD has not defined an acceptable level of risk—relative to the length of time during which units remain committed to augmenting combatant commanders’ needs—DOD lacked reasonable assurance that extending the ballistic missile defense unit’s deployment would not surpass an acceptable level of risk to mission for either of the GRF’s uses. Two other units with capabilities particularly suited for use as part of a joint force have also been deployed individually to augment combatant command capabilities. One is U.S. Transportation Command’s Joint Enabling Capabilities Command, which provides joint communications, planning, and public affairs support to a joint force or joint task force headquarters. A second is U.S. Transportation Command’s Joint Task Force – Port Opening, which provides capabilities able to deploy within 12 to 36 hours to support the opening of a port, including the capability to rapidly establish and initially operate an aerial or sea port of debarkation, conduct cargo handling and movement operations to a forward distribution node, and facilitate port throughput in support of contingency operations. Like ballistic missile defense units, these two units are limited in number. According to officials from U.S. Transportation Command, because the units have been used primarily to augment geographic combatant command capabilities, they are at times unavailable for use as part of a tailorable joint force that can be used to respond quickly to unforeseen worldwide contingencies. Because DOD has not defined the risk it assumes in its use of GRF units, it cannot determine the likelihood that units used to augment combatant commanders’ needs might be required to constitute a joint force composed of GRF units, nor has DOD defined the significance of the risk it incurs by not having a given capability available to the GRF. Further, although DOD has used the GRF primarily to augment combatant commanders’ needs, risks for both uses should be identified and analyzed appropriately since neither use is prioritized over the other. While DOD did not encounter issues accessing GRF units that it required during any of the three instances in which the GRF was deployed as part of a joint force, Joint Staff officials have nonetheless raised an issue concerning the degree of risk that DOD continues to assume by using GRF capabilities to augment combatant commander needs that may be needed by the GRF to constitute a joint force. DOD officials stated that using GRF units to augment geographic combatant command requirements leaves them unavailable for use as part of a joint force ready to respond to an unforeseen worldwide contingency. They stated that this is largely due to the fact that some GRF units are limited in quantity but in high demand worldwide. For example, according to DOD officials, while intelligence, surveillance, and reconnaissance systems are in such high demand that they are consistently used to augment combatant commanders’ requirements, they are also typically used as an essential part of a joint force. As such, there is a likelihood that a GRF joint force might require, but not have access to these capabilities, thus potentially increasing the risk of not accomplishing a given mission. DOD officials stated that in the event of a crisis requiring the employment of GRF units as part of a joint task force, GRF units currently employed elsewhere could be reassigned. It is uncertain, however, whether such reassignment would enable a GRF joint task force to meet its timeframes for deployment given that GRF units are expected to be ready for deployment on very short notice. Moreover, the potential effect of and risks associated with such an occurrence—specifically, the unavailability of required forces to assemble GRF units as part of a joint force—has not been assessed. The identification and analysis of risks provides the basis for developing appropriate risk responses, such as, in this case, further defining and prioritizing the GRF’s intended uses and missions. Because DOD has not identified or analyzed risks associated with the uses of the GRF, it may lack reasonable assurance that this response will be sufficient to mitigate the risks. Further, without identifying risk, DOD is not well positioned to develop other risk-mitigating strategies, and to know when to activate them. Standards for Internal Control in the Federal Government establish that management should assess risks related to achieving defined objectives. Specifically, the standards state that management should analyze the identified risks to estimate their significance and define tolerances for levels of risk assumed, thereby providing a basis for responding to the risks. The standards also call for management to design responses such that risks are contained within the defined risk tolerance for the identified objective. DOD has not assessed the risks to readiness for mission scenarios that it might assume for both uses of the GRF because of its general reliance upon the GRF as an augmentation capability available to individual geographic combatant commands for response to unforeseen challenges or opportunities. Furthermore, we found that there are varying perspectives within DOD concerning the intended uses of the GRF, although the GRF EXORD generally identifies two overarching uses, as previously discussed. Specifically, officials from the Office of the Under Secretary of Defense for Personnel and Readiness and the Joint Staff stated the view that the GRF is a menu of forces, each unit possessing unique capabilities that can be used either individually to address geographic combatant command-identified capability gaps or collectively as a joint force to react to unforeseen worldwide contingencies. However, officials from U.S. Africa Command and U.S. Central Command view the GRF primarily as a pool from which they can draw forces, and it is these geographic combatant commands that have most often requested those capabilities provided by individual GRF units. Officials from the Army expressed another perspective, based in large part on the requirement for the Army to provide a joint task force headquarters for the GRF. Army officials said that, in their view, the GRF serves primarily as a pool of forces from which a joint task force can be created to meet unforeseen worldwide contingencies. Although the GRF EXORD generally identifies the two uses, it does not prioritize the use of GRF assets to meet either. Additionally, DOD has not defined the risk to meeting the objectives of either of the two uses, and, thus does not have the necessary knowledge to determine when to deploy units for one use or the other. As previously stated, DOD has used the GRF to augment combatant commanders’ forces more frequently—32 out of 35 deployments—rather than retaining the units assigned to the GRF to support a rapidly deploying joint force. Conducting a risk assessment that identifies any risks associated with the use of the GRF could help DOD to design responses, such as further defining and prioritizing the GRF’s intended uses and missions in an effort to mitigate any identified risks. Without conducting a risk assessment and taking steps to address any identified risk to accomplishing either of the GRF’s uses, DOD’s attempt to satisfy one of the two intended uses of the GRF may inadvertently hamper the other intended use. GRF units train individually to meet GRF missions, but there are no GRF- specific joint training exercises, and the individual GRF units have limited opportunities to train as part of an integrated joint force, according to DOD officials. Specifically, according to service officials, GRF readiness, and that of assigned units, is based on the assigned force’s participation in their respective service training exercises and are generally focused on the respective units’ core missions or functions. In addition to service- level training, GRF units can also participate in joint training exercises sponsored by one of the geographic combatant commands. These commands can give authoritative direction to subordinate commands and forces necessary to carry out missions assigned to the command, including over all aspects of joint training. However, if GRF units are service retained or assigned to different combatant commands, they would not all fall under the authority of a single commander that could direct joint training. According to military service officials, there are no GRF-specific joint training exercises. However, according to some combatant command officials, some joint training exercises have included units currently assigned to the GRF. Few, if any of these exercises, however, provide opportunities to conduct training for the GRF’s joint task force headquarters in conjunction with GRF-assigned units. For example, according to U.S. Southern Command officials, the Joint Staff’s 2017 Joint Task Force Forming Exercises will be held in U.S. Southern Command’s area of responsibility, and will include the unit currently assigned as the GRF’s Joint Task Force headquarters. However, the exercise will not include any other GRF-assigned units. Therefore, the training will not provide an opportunity for the GRF to demonstrate readiness, gain efficiencies, or identify deficiencies associated with deploying elements of the GRF as a tailorable joint task force. Chairman of the Joint Chiefs of Staff Instruction 3500.01H, Joint Training Policy for the Armed Forces of the United States, notes that U.S. forces may be employed across the range of military operations, and that DOD must support national security requirements with joint military capabilities designed to adapt and succeed in any operational environment. It further states that the department and its mission partners must prepare to operate in a joint, interagency, intergovernmental, and multinational environment. Finally, it notes that the joint training challenge is to be responsive to all emerging and extant mission requirements of the combatant commanders. The need for interoperability is especially important for units assigned to the GRF not only because the GRF EXORD requires that they be ready for eight global mission scenarios, but because the overall GRF concept suggests they need to be capable of integration into a tailorable joint force. Underscoring this need for interoperability and jointness, the GRF EXORD outlines that combatant commanders should integrate elements of the GRF into Joint Exercise Program events to help sustain the readiness and capabilities of those units to execute various mission capability requirements. It also notes that combatant commanders should conduct a training event with the GRF’s Joint Task Force-capable headquarters at least once every 30 months in order to maintain the headquarters’ readiness to support each geographic combatant command. While these requirements are important to ensure the GRF units receive the proper training and are integrated into combatant command joint exercises, there are no specific GRF joint training exercises that provide opportunities for individual units assigned to the GRF to train as a tailorable joint task force. Joint Staff and service officials told us that the GRF’s assigned forces do not require additional or special training because they will perform the core missions for which they train regardless of whether they are deployed individually or as part of the GRF joint task force. These officials stated, therefore, that existing training is sufficient to develop and determine readiness of the GRF. However, the importance of exercising the GRF Joint Task Force headquarters and associated GRF-assigned units was demonstrated to us when we observed an Army-sponsored joint training event involving GRF-assigned forces during a January 2017 Deployment Readiness Exercise at Fort Bragg, North Carolina, during which several interoperability challenges arose. For example, the Army and Air Force faced a challenge in calculating the weight of Army heavy equipment being loaded onto Air Force aircraft preparatory to a simulated airdrop mission. Based on the Army’s calculations, the equipment load was well under the specified weight limit for the aircraft, but the Air Force’s onboard computers showed the load as being over the limit. While the cause of the difference in the two figures was not identified to us at the time, Army officials suspected that it could be attributed to a double-counting of the weight of the parachute. In another example, inclement weather at Fort Bragg during the exercise caused ice build-up on participating aircraft. This showed that the Air Force’s de-icing capability was limited to a few aircraft at a time, which caused delays in loading and preparing the aircraft for take-off. According to Army officials, had the mission required more personnel, equipment, and aircraft, this issue would have created a risk to meeting the GRF’s mission timelines. Despite the challenges encountered during the exercise, Army officials told us that exercises, such as the Deployment Readiness Exercise conducted at Fort Bragg, are important because they give units from different services the opportunity to identify challenges and develop solutions. As a result, these exercises can enhance the GRF’s joint task force capability. Additionally, a senior official from the Office of the Under Secretary of Defense for Personnel and Readiness’ Force Training Directorate told us that the ability to act jointly was very important in military operations and noted the need for joint training. Two studies conducted on behalf of DOD further underscore the importance of joint exercises for developing GRF force readiness. The first study, released by the Institute for Defense Analysis in 2015, reported that the current joint exercise program did not ensure a proficient and ready GRF. Specifically, the study identified three key issues associated with GRF training. First, realistic interoperability training of individual units assigned to the GRF was not sufficient to ensure overall GRF readiness. Second, while the then-current version of the GRF EXORD assigned joint training responsibilities to the services, according to the study, the service responsible for the Joint Task Force-capable headquarters element lacked the authority to direct the required level of joint training for GRF elements provided by other services. Third, the GRF, in its entirety, had not been exercised or deployed as a joint force since its inception and thus had not demonstrated the ability to rapidly deploy as an operationally coherent joint task force. The report recommended that DOD designate a single commander with authority to establish and enforce joint integrated training at the tactical level, make changes to improve training for the GRF’s Joint Task Force headquarters, and implement a joint demonstration campaign for the GRF. According to Joint Staff officials, they are not aware of any actions taken in response to these recommendations. The second study, released by RAND in 2016, also emphasized that realistic exercises were key to ensuring and validating the GRF’s readiness. The report added that current exercises rarely included full and realistic force packages and recommended that joint airborne exercises be designed explicitly to identify and assess the implications of possible challenges and validate planning assumptions about a GRF joint task force. According to Army officials, a major factor inhibiting joint training exercises focused at GRF-assigned units as a joint task force is the fact that it can be difficult to get other services to agree to participate in service-sponsored events because—as the Institute for Defense Analysis study pointed out—services lack the authority to direct other services to supply forces for joint training exercises, even when those forces are currently on a GRF rotation. Moreover, since the disestablishment of U.S. Joint Forces Command in 2011, which was responsible, among other things, for being the lead agent for joint force training, there is no single commander with the authority to require joint force training. As noted above, although geographic combatant commanders may direct joint training of forces under their command, units designated for the GRF mission may come from forces assigned to different geographic combatant commands or service-retained forces, according to officials. According to a senior Office of the Under Secretary of Defense for Personnel and Readiness’ Force Training Directorate official, the challenge to conducting joint GRF training is that there is no entity having authority and responsibility for such training. He noted that because the GRF is department-wide and is not assigned to a single service or geographic combatant command, there is no single advocate for the GRF mission and training with the authority to direct the services and geographic combatant commands with GRF-dedicated units to prepare for the joint requirements inherent in the GRF mission. As a result, there are no joint training exercises specifically designed to exercise GRF units as a joint force. According to Standards for Internal Control in the Federal Government, management should develop an organizational structure with an understanding of the overall responsibilities, and assign these responsibilities to enable the organization to operate in an efficient and effective manner, comply with applicable laws and regulations, and reliably report quality information. To achieve this, management should assign responsibility and delegate authority to key roles throughout the entity. Without an entity having the responsibility and authority to plan, direct, and conduct joint training exercises focused on GRF-assigned units deploying as a joint task force as appropriate, DOD risks undermining the effectiveness of the rapid deployment of a GRF joint task force in response to unforeseen worldwide contingencies. DOD has developed the GRF as a rapid response force available to react to unforeseen contingencies or crises. While the GRF has responded to worldwide contingencies, GRF units have been primarily used to augment existing geographic combatant command capabilities. DOD has not assessed the risks it assumes by its reliance upon the GRF for augmenting combatant commanders’ forces as opposed to having the GRF-assigned units available for allocation to a joint task force in response to a contingency. Without performing a risk assessment and, as appropriate, designing responses to mitigate any identified unacceptable risks to accomplishing either of the two GRF uses, DOD cannot ensure that the GRF is able to meet its mission. Additionally, without a designated authority to establish and enforce integrated joint training for GRF-assigned units as appropriate, DOD has not developed GRF- specific joint training exercises or fully integrated the GRF into existing joint exercises. Without making improvements in these areas, DOD risks the ability of the GRF to respond to unforeseen, worldwide contingencies as an integrated joint force in a timely fashion with all the resources it needs. We are making the following three recommendations to DOD: The Secretary of Defense, in conjunction with the Chairman of the Joint Chiefs of Staff, should assess the risks to accomplishing both of the GRF’s uses: that is, its use as an augmentation capability available as needed to individual geographic combatant commands; and its use as a tailorable joint force available for rapid response to a specific threat. (Recommendation 1) The Secretary of Defense, in conjunction with the Chairman of the Joint Chiefs of Staff, should, as appropriate following the assessment of risk, design responses, such as further defining and prioritizing the GRF’s intended uses and missions, to mitigate any identified risks. (Recommendation 2) The Secretary of Defense, in conjunction with the Chairman of the Joint Chiefs of Staff, should designate an authority to establish and enforce integrated joint training for GRF-assigned units, as appropriate. (Recommendation 3) We provided a draft of this report to DOD for review and comment. In its written comments, DOD concurred with our three recommendations and noted planned actions to address them. DOD’s comments are reprinted in their entirety in appendix II. We are sending copies of this report to the appropriate congressional committees; the Secretary of Defense; the Under Secretary for Personnel and Readiness, the Chairman of the Joint Chiefs of Staff; the Secretaries of the Army, the Navy and the Air Force; and the Commandant of the Marine Corps. In addition, the report will be available at no charge on the GAO Web site at http://www.gao.gov. If you or your staff have any questions about this report, please contact me at (202) 512-5431, or russellc@gao.gov. Contact points for our Offices of Congressional Relations and of Public Affairs may be found on the last page of this report. GAO staff who made major contributions to this report are listed in appendix III. The objectives of our review were to examine the extent to which (1) Department of Defense (DOD) has used the Global Response Force (GRF) and assessed any risks associated with its use; and (2) GRF- assigned units are trained to meet GRF missions, both individually and as a joint force. For our objective of determining the extent to which DOD has used the GRF and assessed any risks associated with its use, we reviewed the Chairman of the Joint Chiefs of Staff GRF Execute Order (EXORD) to identify the GRF’s overall uses and the global mission scenarios it is intended to meet, as well as the operational requirements and forces assigned to meet the requirements. We also interviewed the responsible DOD officials to understand how DOD selects, designates, and validates forces on the GRF, and the processes for making changes to the GRF EXORD, as well as how DOD decides when to use GRF forces for either of the two intended uses of the GRF. Also, we reviewed Standards for Internal Control in the Federal Government to identify relevant internal controls—specifically, that management should assess risks related to achieving defined objectives, analyze the identified risks to estimate their significance, define tolerances for levels of risk assumed, and design responses such that risks are within the defined risk tolerance—and compare them with DOD’s risk assessment efforts for the GRF. Also, we reviewed the Joint Staff’s GRF deployment information from 2010 to 2017 to understand the frequency of GRF deployments and identify specific instances in which the GRF’s ability to accomplish its missions was affected—specifically, instances in which GRF capabilities were unavailable for use during a GRF operation. For our objective of determining the extent to which GRF-assigned units are trained to meet GRF missions, both individually and as a joint force, we reviewed the Chairman of the Joint Chiefs of Staff GRF EXORD and DOD’s Guidance for the Defense Readiness Reporting System to understand how GRF readiness is developed, reported, and evaluated. We also reviewed DOD’s Joint Training Policy for the Armed Forces of the United States to identify existing requirements related to joint training, and documents related to GRF training to determine the extent to which the frequency and types of GRF training meet overall joint training requirements as well as training requirements established in the GRF EXORD. We observed a Deployment Readiness Exercise at Fort Bragg, North Carolina, to learn about the types of GRF training, as well as challenges and potential benefits of training exercises for GRF units. We also interviewed senior officials from the Joint Staff, military service force providers, and geographic combatant commands to better understand training practices for the GRF and its assigned units, as well as varying perspectives regarding the challenges and potential benefits of GRF training exercises for accomplishing GRF missions. We interviewed senior officials from the Office of the Under Secretary of Defense for Personnel and Readiness; Joint Staff; and Army, Marine Corps, Navy, and Air Force headquarters, and conducted site visits to force providers at Army Forces Command, Marine Forces Command, Navy Fleet Forces Command, Air Force Air Combat Command, and U.S. Transportation Command. We also interviewed officials from U.S. Africa Command, U.S. European Command, and U.S. Pacific Command, and visited U.S. Central Command and U.S. Southern Command. Our interviews focused on understanding the degree to which DOD organizations assess and maintain a consistent understanding of the risks entailed in using GRF forces and gaining an understanding of the challenges encountered in identifying, designating, and employing forces on the GRF, as well as the extent to which the GRF’s ability to accomplish its intended missions has been affected. We conducted this performance audit from May 2016 to October 2017 in accordance with generally accepted government auditing standards. Those standards require that we plan and perform the audit to obtain sufficient, appropriate evidence to provide a reasonable basis for our findings and conclusions based on our audit objectives. We believe that the evidence obtained provides a reasonable basis for our findings and conclusions based on our audit objectives. In addition to the contact named above, individuals who made key contributions to this report include Guy LoFaro, Assistant Director; Adam Anguiano; Alberto Leff; Michael Shaughnessy; Michael Silver; Yong Song; and Cheryl Weissman.

Summary: DOD must be able to rapidly deploy forces to respond to a range of worldwide contingencies, and in 2007 it established the GRF to enhance that capability. The GRF is a set, or “menu,” of forces from the military services, each of which possesses unique capabilities, and which the Secretary of Defense can deploy rapidly anywhere in the world. House Report 114-537, accompanying a bill for the National Defense Authorization Act for Fiscal Year 2017, included a provision for GAO to evaluate challenges DOD may be facing regarding the GRF. GAO reviewed the extent to which (1) DOD has used the GRF, and assessed any risks associated with its use of the GRF; and (2) GRF-assigned units are trained to meet GRF missions individually and as a joint force. GAO reviewed GRF deployment information from 2010 to 2017 and the GRF Execute Order, observed a training exercise, and interviewed knowledgeable officials. The Department of Defense's (DOD) Global Response Force (GRF) has two distinct uses: one is to enhance DOD's ability to rapidly deploy forces in response to a range of worldwide contingencies with a tailorable joint force; and the other is to provide a set, or “menu,” of units that combatant commands can request to augment their capabilities in light of unexpected challenges when requirements exceed their capabilities. Since 2010, according to officials, DOD has used the GRF 35 times in support of worldwide contingencies, with 32 of those times involving deployment of individual GRF units to augment combatant commander needs, and 3 times involving their use as part of a joint task force. This predominant use of individual GRF units to augment combatant commanders' needs has diminished the set of units available for mission scenarios related to the GRF's use as a tailorable joint force. For example, when DOD deployed a ballistic missile defense unit as a part of the GRF to augment a combatant command's missile defense capabilities, the particular capability it supplied to the GRF was not available for participation in a tailorable joint force to respond quickly to a potential worldwide contingency, if such an event occurred. DOD does not know what risks it assumes to readiness for GRF mission scenarios due to its general reliance upon the GRF as an augmentation capability available to individual geographic combatant commands, because DOD has not assessed those risks. Without conducting a risk assessment and taking steps to address any identified risk to accomplishing the GRF's intended uses, DOD's attempt to satisfy one of the uses (that is, individual GRF-assigned units assisting combatant commands) may hamper the other use (that is, deployment of a joint task force for a contingency). GRF units train individually to meet GRF missions, but DOD does not conduct any GRF-specific joint training exercises, and the individual GRF units have limited opportunities to train as part of an integrated joint force, according to DOD officials. While the GRF Execute Order calls for integrating elements of the GRF into existing joint training, the military services lack the authority to direct other services to supply forces for joint training exercises, even when those forces are currently on a GRF rotation. Moreover, since the disestablishment in 2011 of U.S. Joint Forces Command—which, among other things, was the lead agent for joint force training—and because units designated for the GRF mission may be assigned to different combatant commands or may be service-retained, no single commander has the authority to require joint force training of GRF units. As a result, no joint training exercises are specifically designed to exercise GRF units as a joint task force. Army officials told GAO that joint exercises are important because they give individual units from different services the opportunity to identify challenges and develop solutions, thereby enhancing the GRF's joint task force capability. Without an entity having the responsibility and authority to plan, direct, and conduct joint training exercises focused on GRF-assigned units deploying as a joint task force as appropriate, DOD risks undermining the effectiveness of the rapid deployment of a GRF joint task force in response to unforeseen worldwide contingencies. GAO recommends that DOD (1) assess the risks assumed in its reliance upon the GRF as both an augmentation capability and a tailorable joint force; (2) design appropriate responses following the risk assessment; and (3) designate an authority to establish and enforce integrated joint training as appropriate for GRF-assigned units. DOD concurred with GAO's three recommendations.