The Office of Personnel Management (OPM) is tasked with providing human resources, leadership, and support to federal agencies to manage their human capital functions. For OPM to effectively perform this role, executive branch agencies are required to report information on their civilian employees to OPM and ensure that workforce data meet certain standards developed by OPM. OPM has developed these data to carry out its strategic goal of serving as a thought leader in data-driven human resource management and policy decision-making. The Enterprise Human Resources Integration (EHRI) system is OPM’s primary repository for human capital data to support these efforts. OPM developed EHRI to (1) provide for comprehensive knowledge management and workforce analysis, forecasting, and reporting to further strategic management of human capital across the executive branch; (2) facilitate the electronic exchange of standardized human resources data within and across agencies and systems and the associated benefits and cost savings; and (3) provide unification and consistency in human capital data across the executive branch. In addition, OPM’s updated system and integrated data were expected to accrue savings to the federal government, reduce redundancy among agency systems, streamline the various processes involved in tracking and managing federal employment, and facilitate human capital management activities by providing storage, access, and exchange of standard electronic information through a data repository of standardized core human capital data for most executive branch employees. While the personnel database predated the EHRI Data Warehouse, the payroll database was newly developed for OPM’s e-payroll initiative to consolidate agency payroll processes. The payroll database contains individual payroll records for approximately 2.0 million federal employees and is the primary governmentwide source for payroll information on federal employees. The records consist of data elements such as an EHRI ID for linking files, agency time charge categories, and pay rates. The consolidation of agency payroll processes—known as the e-payroll project—provided the opportunity for OPM to begin collecting standardized governmentwide payroll data. As part of the e-payroll initiative, OPM consolidated the operations of 22 federal payroll system providers for the 116 executive branch agencies into four primary providers—General Services Administration’s (GSA) National Payroll Center (NPC), the Department of Defense’s Defense Finance and Accounting Service (DFAS), Department of Interior’s Interior Business Center (IBC), and Department of Agriculture’s National Finance Center (NFC). Consolidation was undertaken to simplify and standardize federal payroll policies and procedures, and better integrate payroll with other human capital and finance functions. Most federal agencies rely on one of the four payroll service centers, DFAS, IBC, NPC, or NFC, to process employee pay. Payroll service centers receive employees’ bi-weekly time sheets which come from a variety of time and attendance (TA) systems from the agencies they service. Generally, TA systems allow employees to specify time spent on different work and leave categories, such as the number of regular or overtime hours worked or the number of annual leave or sick leave hours taken in a given pay period (PP). However, the level of detail regarding the exact nature of the work or leave time varies depending on agency policies and systems for recording employee work time. While the service centers have consolidated payroll reporting, there are still variations among the centers and the TA systems agencies use to submit employee time sheets. Some systems are maintained by the service center and employees from various agencies access those systems to record their hours. For example, GSA has only one TA system that agencies use to record work and leave hours. Other systems are maintained by the agency and may reflect specific TA accounting needs of the agency. For example, NFC processes time sheets from several different TA systems, some of which are agency specific, and DFAS processes payroll for the Department of Defense, Veterans Affairs, and others through systems including the Business Management Redesign (e-Biz) TA system and the Automated Time, Attendance, and Production System (ATAAPS) (see figure 1). In light of the significant variation in TA systems and service centers involved in processing TA information into payroll records, OPM established core standards for consistency in reporting and recording certain types of work and leave hours. These standards apply at the agency level as well as the service center level. Some of these standards are based on official leave authorized in statute. For example, federal employees are authorized to be absent from duty without a loss in pay or charge to leave for legal holidays and for activities such as jury duty, attendance at a military funeral, bone-marrow or organ donation, and certain union activities. Other standards are based on OPM guidance for excused absences due to inclement weather or blood donation, among others, charged as administrative leave. Agencies follow common recording practices for annual leave and sick leave. These core standards at the agency level are an important part of the process for reporting to OPM because they allow the service centers to collapse certain fields in a consistent way. While agencies may have specific time codes and time keeping practices to meet their needs, core standards for service center reporting dictate how these codes should be collapsed for reporting to OPM. For example, agencies may have detailed categories for various types of administrative leave, but segments of those charge codes apply generally to the category of administrative leave, enabling service centers to aggregate these data from TA systems. OPM relies on agencies and service centers to ensure that the data they submit are timely, accurate, complete, and compiled in accordance with OPM standards. However, federal internal control standards specify that even when external parties, such as service centers in this case, perform operational processes for an agency, management—in this case OPM— retains responsibility for the performance of responsibilities assigned to those organizations. Consequently, OPM management is responsible for understanding the controls each service center has designed, implemented, and operates for payroll processing and how the service centers’ internal control systems impact OPM’s internal controls for the payroll data. Underlying requirements for data standards and data quality efforts are the standards for internal control which apply to all executive branch government functions. According to Standards for Internal Control in the Federal Government , effective internal control systems have certain attributes, including reliable internal and external sources that provide data that are reasonably free from error and bias and faithfully represent what they purport to represent. Another attribute involves management evaluating both internal and external sources of data for reliability, and obtaining data on a timely basis so that they can be used for effective monitoring. Use of the EHRI payroll database has been limited because OPM has not made it widely available. This is in contrast to other, related OPM datasets, such as the EHRI personnel database, which OPM has prepared for use and made publicly available through multiple mechanisms including FedScope, an online tool for data analytics. Because the EHRI payroll database has potential to be used for accountability, research, and data-driven human resource management and policy decision making, making it available would support OPM’s strategic and open data goals. The EHRI payroll data have rarely been used since the database became operational in 2009. We identified four instances where the data have been used, primarily by OPM or by GAO to respond to Congressional requests for information. Specifically, (1) OPM used EHRI payroll data to calculate rough estimates of official time—paid time that employees spend on union-related activities—for its 2009 to 2012 reports to Congress; (2) we made similar use of EHRI payroll data to estimate use of official time in selected federal agencies in a 2014 report, which revealed limitations in OPM’s method of estimating the governmentwide costs of official time; (3) we used EHRI payroll data in a 2014 review that found inconsistencies in how agencies recorded and reported the use of administrative leave; and (4) we used EHRI payroll data in 2016 to report on the use of administrative leave at the Department of Homeland Security (DHS). In this final case, our use of EHRI data enabled a more detailed examination of DHS’s use of administrative leave and helped verify the reliability of the information obtained from DHS. Aside from these four instances, the data remain largely unused because OPM does not make the data available to the larger research community or to federal agencies. This is in contrast to other OPM data, such as the EHRI personnel data, which has been widely used since OPM made it available. OPM has taken specific steps to make these other human resources-related data available, but has not taken any of these steps for the EHRI payroll database. For example, OPM has made the EHRI personnel database available by (1) cleaning it and preparing it for statistical analysis; (2) integrating it with other data in a repository known as the EHRI Statistical Data Mart; (3) making deidentified data—that is, data without personally identifiable information—accessible through FedScope, an online data analytics tool that draws on data in the Statistical Data Mart; (4) listing data that are available (either by download or by request) on the OPM website and on Data.gov; and (5) sharing requested data with other parties, such as think tanks and academic researchers. Data in the EHRI Statistical Data Mart are also processed and repackaged to make them more available and usable. Specifically, data received by OPM from agencies and stored in the EHRI Data Warehouse are further processed and cleaned and placed into a format better suited for analysis. This process involves additional corrections and generates additional data elements likely to be useful for statistical analysis. These processed and prepared data are then submitted to the EHRI Statistical Data Mart, which forms the basis for FedScope. Both the FedScope analytics tool and the downloadable datasets are accompanied by documentation that clarifies the meanings of the data elements and limitations associated with the data. OPM also makes other EHRI data available through its website and Data.gov.