Four major principles currently underlie U.S. policy for admitting lawful permanent residents (LPRs): reunifying families, admitting individuals with needed skills, providing humanitarian assistance, and diversifying immigrant flows by country of origin. These principles are expressed in the Immigration and Nationality Act (INA), which contains a pathway for acquiring LPR status for each principle. Family reunification occurs primarily through family-sponsored immigration. Admitting individuals with needed skills occurs through employment-based immigration. Humanitarian assistance occurs primarily through the U.S. refugee and asylum programs. Origin-country diversity occurs primarily through the Diversity Immigrant Visa. This report focuses on the second LPR pathway noted above, employment-based immigration. Employment-based immigrants enter the United States through one of five preference categories, each with its own eligibility requirements and numerical limitations and, in some cases, different application processes. In addition to the numerical limits imposed upon each preference category, employment-based immigrants face a per-country ceiling, or "cap," that limits the number of immigrants from any single country of origin to 7% of the annual limit for each of the five preference categories. This limitation was imposed to prevent any one country or handful of countries from dominating the flow of employment-based immigration to the United States. The numerical limits imposed upon each preference category, combined with the per-country ceiling, mean that employment-based immigrants from certain countries can face considerable waits before they can acquire LPR status. In recent years, some Members of Congress have shown interest in reassessing the 7% per-country ceiling for employment-based immigration. Some assert that the current numerical limits on employment-based LPRs are not working in the national economic interest and potentially lead to exploitation of foreign workers who are waiting to acquire LPR status. Others argue that such limits prevent a few countries from dominating employment-based immigration. The report opens with explanations of the employment-based preference categories and the per-country ceiling governing annual permanent immigration. It then presents trend data on employment-based immigration. Focusing primarily on the five major employment-based preference categories, the report continues by analyzing pending queues of six distinct pools of petitions and applications found across the administrative process of acquiring employment-based LPR status. The report then presents arguments for and against removing the per-country ceiling on employment-based LPRs. It discusses recent congressional proposals to alter the per-country ceiling, and considers possible outcomes that might occur as a result of eliminating it. The INA limits worldwide permanent immigration to 675,000 persons annually: 480,000 family-sponsored immigrants, made up of family-sponsored immediate relatives of U.S. citizens (immediate relatives), and a set of four ordered family-sponsored preference immigrant categories ("preference immigrants"); 140,000 e mployment-based immigrants comprised of a set of five preference immigrant categories and 55,000 diversity visa immigrants . This worldwide limit, however, is referred to as a "permeable cap" because immediate relatives are exempt from numerical limits placed on family-sponsored immigration and thereby represent the flexible component of the 675,000 worldwide limit. Consequently, the actual total of foreign nationals receiving LPR status each year (including immigrants, refugees, and asylees) has averaged roughly 1 million persons during the past decade. The INA further specifies a "per-country ceiling," or "cap," limiting the number of family-sponsored preference immigrants and the number of employment-based immigrants from any single country to 7% of the limit in each preference category. The per-country level is not a "quota" set aside for individual countries, as each country in the world could not receive 7% of the overall limit. The Department of State (DOS) notes that "the country limitation serves to avoid monopolization of virtually all the annual limitation by applicants from only a few countries," and is not "a quota to which any particular country is entitled." The INA outlines five distinct employment-based preference categories and their individual numerical limits within the overall worldwide total of lawful permanent residents. How prospective immigrants apply for employment-based LPR status depends on where they reside. They may apply directly from abroad as new immigrant arrivals or from within the United States as "status adjusters." Adjusting status refers to the process of changing from a temporary (nonimmigrant) status (e.g., F-1 student visa, H-1B skilled temporary worker visa) to LPR status. In either case, petitioning and application involve multiple steps and federal agencies. While some prospective employment-based immigrants can self-petition, most require U.S. employers to petition on their behalf. DOS and the Department of Homeland Security (DHS) each play key roles in administering the law and policies on immigrant admission. In addition, petitioners for 2 nd and 3 rd preference category immigrants must apply for labor certification (described below) from the Department of Labor (DOL). Once any required labor certification is approved, DHS's U.S. Citizenship and Immigration Services (USCIS) must adjudicate an immigrant petition. If the prospective immigrant resides in the United States, USCIS also processes the application to adjust to LPR status (discussed below). In contrast, if the prospective immigrant resides abroad, they must subsequently apply to DOS's Bureau of Consular Affairs for a visa to travel to the United States. DOS is also responsible for the allocation, enumeration, and assignment of all numerically limited "visa numbers" or slots, regardless of where prospective immigrants reside. Among prospective immigrants, the INA distinguishes between principal prospective immigrants (principals) who meet the qualifications of the employment-based preference category, and derivative prospective immigrants (derivatives) who include the principals' spouses and children. Derivatives appear on the same petition as principals and are entitled to the same status and order of consideration as long as they are "accompanying" or "following to join" principal immigrants. Employment-based LPR status is granted to eligible immigrants in the order in which immigrant petitions have been filed under the specific employment-based preference category for the origin country. Visa numbers are prorated according to the preference system allocations ( Table 1 ). The INA provides for certain adjustments within the numerical limits imposed for each of the five employment-based preference categories. First, unused visa numbers for each of the preference categories can "roll down" and be used by immigrants applying in the next preference category. Second, in any given quarter, if the number of available visa numbers exceeds the number of applicants, then the per-country ceiling does not apply for the remainder of available visa numbers for that quarter. Third, any unused family-based preference immigrant visa numbers can be applied to employment-based preference immigrant visa numbers in the next fiscal year. Due to numerical limitations for each preference category, the number of approved immigration petitions for a specific preference category in a given year may exceed visa numbers available for that category as well as the country of origin (due to the 7% per-country ceiling). As a result, individuals with approved petitions may be placed in a queue until a visa is available (see " Pools of Prospective Employment-Based LPRs "). DOS's Visa Bulletin for December 2018 presents action dates (also known as "cut-off dates") for employment-based preference immigrants ( Table 2 ). If a date appears for any preference category, it indicates that the category is "oversubscribed" and that a numerically limited visa number is available only to prospective employment-based immigrants with priority dates that are on or earlier than that cut-off date. Such prospective employment-based immigrants are eligible to submit their visa application to DOS or their adjustment of status application to USCIS. The term "current" indicates that DOS can issue visa numbers to all qualified applicants in that category regardless of priority date or country of origin. Usually cut-off dates in the Visa Bulletin advance with time. However, visa number demand by applicants with a variety of priority dates can fluctuate from month to month, invariably affecting cut-off dates. Such fluctuations can cause cut-off date movement to slow or stop. In some cases where visa number demand unexpectedly exceeds supply, DOS may have to regress cut-off dates to earlier dates to maintain an orderly queue, a situation referred to as "visa retrogression." In sum, visa retrogression occurs when more people apply for a visa number in a particular category or country than there are visa numbers available for that month. Priority dates shown in the Visa Bulletin are not necessarily an accurate guide for visa applicants to gauge their expected wait times until they can apply for a visa or adjust status. Changes in the rate at which foreign nationals apply for LPR status can alter waiting times substantially. For example, the Visa Bulletin for December 2018 indicates that Indian nationals, whose 2 nd preference employment-based petitions (professionals with advanced degrees) were submitted on or before April 1, 2009, could apply for a visa. Indian nationals who were considering applying as employment-based immigrants might interpret this to mean that filing a 2 nd preference employment-based immigrant petition in December 2018 would result in an expected wait time of about 9.5 years until they could receive LPR status. However, if more or fewer Indian nationals applied for employment-based LPR status between 2009 and 2018 than those who applied for LPR status during the 9.5 years prior to April 1, 2009, expected wait times for LPR status could be longer or shorter, respectively. Before petitioning for 2 nd and 3 rd preference category workers, employers must first apply for a foreign labor certification from DOL. To grant it, DOL must determine through its foreign labor certification program that (1) there are insufficient able, willing, qualified, and available U.S. workers to perform the work in question; and (2) the employment of foreign workers will not adversely affect the wages and working conditions of similarly employed U.S. workers. Following this step, sponsoring employers and self-petitioning individuals must file one of three employment-based immigrant petitions with USCIS: an Immigrant Petition for Alien Workers (USCIS Form I-140) for 1 st , 2 nd , and 3 rd preference categories; a Petition for Amerasian Widow(er), or Special Immigrant (USCIS Form I-360) for the 4 th preference category; and an Immigrant Petition by Alien Entrepreneur (USCIS Form I-526) for the 5 th preference category. USCIS sends processed and approved immigrant petitions to DOS's National Visa Center (NVC), which assigns a priority date (the petition filing date) that represents the prospective immigrant's place in the visa queue. Individuals must wait for their priority date to "become current" before proceeding. Priority dates become "current" when they are earlier than the "final action dates" (often referred to as the "cut-off dates") published for the five numerically limited, employment-based immigrant preference categories in DOS's monthly Visa Bulletin (see Table 2 below). Once a prospective immigrant's priority date becomes current, the next steps taken depend on whether he or she resides abroad or in the United States. If the prospective immigrant resides abroad, he or she must apply to DOS for a visa to enter the United States with an Application for Immigrant Visa and Alien Registration (DOS Form DS-260). If the prospective immigrant is already residing in the United States, he or she must apply to USCIS to adjust status with an Application to Register Permanent Residence or Adjust Status (USCIS Form I-485). The final stage in the employment-based immigration process is an interview with either a DOS consular official for foreign nationals residing abroad or a USCIS adjudicator for foreign nationals residing in the United States. If the prospective immigrant is living abroad, the DOS consular office in the applicant's home country will schedule an interview with the prospective immigrant to determine if he or she can receive an immigrant visa to come to the United States and seek admission as an LPR, a pathway known as consular processing. Regardless of whether the potential LPR is applying for a visa abroad from a DOS consular office or applying to adjust status with USCIS in the United States, DOS assigns the visa priority dates and allocates the visa numbers. Figure 1 presents the trends in the admission of employment-based immigrants from 1997 to 2017 by preference category. Over this period, the total number of employment-based immigrants fluctuated from a low of 56,817 (in 1999) to a peak of 246,877 (in 2005). In FY2017, these 137,855 employment-based immigrants represented 12% of the 1,127,167 foreign nationals who received LPR status. The data illustrate that, as noted in Table 1 above, the INA allocates most employment-based LPRs to the 1 st , 2 nd , and 3 rd preference categories. The 2003 dip and the 2005 spike in employment-based LPRs resulted from disruptions caused by the transfer of immigration functions from the legacy Immigration and Naturalization Service in the Department of Justice to the new USCIS in the newly created Department of Homeland Security in 2003. The 2005 increase in employment-based LPRs resulted from a provision in the Real ID Act of 2005, which provided for the "recapture" or re-use of past unused employment-based visa numbers. Within the total number of employment-based immigrants, the annual number of employment-based preference LPRs have fluctuated substantially over the two decades. In contrast with all other employment-based preference immigrants, the number of 5 th preference immigrants increased tenfold between FY1997 and FY2017 (from 936 to 9,863), largely from the popularity of the USCIS EB-5 Regional Center Program. Most foreign nationals who became employment-based LPRs in the past two decades were already living in the United States and adjusted to LPR status from some other temporary (nonimmigrant) status ( Figure 2 ). In FY2017, for example, 82% of employment-based LPRs adjusted to LPR status from within the United States; only 18% acquired LPR status as new arrivals from abroad. The 5 th preference immigrant investors were the exception, with a majority being admitted as new arrivals since 2006. As noted above, acquiring LPR status through the INA's employment-based immigration provisions requires a series of administrative steps performed by various federal agencies involving labor certifications, immigration petitions, and visa applications. The following section isolates and describes six distinct groups of LPR petitions and applications in order of administrative processing: pending labor certification applications at DOL, pending immigrant petitions at USCIS, pending approved visa applications at DOS, pending approved adjustment of status petitions at USCIS, visa applications submitted to DOS, and adjustment of status applications submitted to USCIS. Because each step in the process involves some form of review or adjudication, a certain number of petitions or applications in each pool are denied and do not advance to the next step. As such, foreign nationals at the early stages of the employment-based immigration process face a lower likelihood of ultimately obtaining LPR status compared with those near the end of the process. While the six distinct groups of petitions and applications discussed here illustrate the pools of prospective employment-based immigrants at different stages of administrative processing, only two pools represent applicants who are limited from advancing because of the INA's numerical limits. Those two pools (the third and the fourth) include those with approved employment-based immigrant petitions who are either waiting overseas to obtain a visa or waiting in the United States to adjust their status. As such, those two pools represent the employment-based immigration queue. Employment-based immigrant petitions are submitted not only on behalf of principal immigrants who meet the qualifications of the applicable preference category but also on behalf of derivative immigrants (i.e., the spouses and children accompanying or following to join the principal prospective immigrants) who are included in the same petition. In the discussion below of the fourth pool of prospective immigrants waiting to adjust status with USCIS, the number of derivative immigrants is estimated using USCIS data (see " Pending Approved Adjustment of Status Petitions at USCIS "). As noted above, employers who wish to file a petition with USCIS for 2 nd (professionals) and 3 rd (skilled/unskilled) preference category immigrant workers must first obtain a foreign labor certification from DOL. The INA does not impose limits on the number of labor certification requests that DOL can approve, and annual fluctuations in certification application volume generally reflect fluctuating employer labor demand. For FY2018, DOL's Office of Foreign Labor Certification reported receiving 104,360 applications - and processing 119,776 applications from FY2018 and earlier years. Of the applications processed, 109,550 beneficiaries (91%) received certification, 6,255 (5%) were denied, and 3,971 (3%) were withdrawn. Once any required labor certification has been obtained, petitioners file one of three employment-based immigrant petitions (I-140, I-360, or I-526, as described above) with USCIS. As such, this queue represents a workflow of employment-based immigration petitions "in process" that have not yet been approved. Data on petitions in this pool are presented in USCIS processing statistics issued each quarter. As of June 30, 2018 (the most recent date for which data are publicly available), pending employment-based immigration petitions numbered 45,889 for I-140 petitions, 49,898 for I-360 petitions, and 17,126 for I-526 petitions, totaling 112,913 for all three petition types. By comparison, 3 rd quarter pending petitions for these three petition types totaled 115,159 in FY2017 and 81,302 in FY2016. Approval or denial hinges not on any numerical limits imposed by the INA but on whether petitioners have provided sufficient and appropriate documentation and whether the beneficiaries meet the qualifications for the specific preference category. The third pool of pending employment-based applicants includes foreign nationals living abroad with approved employment-based immigrant petitions who are waiting to apply for a numerically limited visa. Unlike the first and second pools above, this pool is limited from advancing to the next administrative step because of numerical restrictions imposed by the INA. This pool is the overseas equivalent to the pool of applicants with approved immigrant petitions waiting to adjust status at USCIS (discussed below). At the end of each fiscal year, DOS' National Visa Center (NVC) publishes a tabulation of persons with approved immigrant petitions who are waiting to apply for a visa. The NVC reported 112,189 pending applications for employment-based LPR visas as of November 1, 2017. Unlike the data on approved immigrant petitions that are pending with USCIS, visa applicants with DOS include both principal petition beneficiaries as well as their derivative spouses and children. Table 3 presents the total number of persons, including derivatives, with approved employment-based immigrant petitions pending with the NVC as of November 1, 2017, by preference category and country of origin. Overall, almost half (47%) were for 3 rd preference "professional and skilled workers." The next two categories with the largest number of pending visa petitions were for 5 th preference employment creation "investors" and 2 nd preference "professionals with advanced degrees or of exceptional ability." Table 3 also shows that China, India, and the Philippines dominate as the source countries for foreign nationals in this queue, comprising over four fifths (82%) of the total. The fourth pool of pending employment-based applications includes foreign nationals already present in the United States with approved employment-based immigrant petitions who have not yet adjusted status. This pool is the domestic equivalent to the pool of applicants with approved immigrant petitions waiting to apply for a visa (discussed above). This pool is the largest of the six discussed in this section. These foreign nationals reside in the United States as legal nonimmigrants, and many work as skilled temporary workers with H-1B visas. Prospective immigrants can only file an adjustment of status application (Form I-485) after DOS has indicated that a visa number is available. Such availability depends on how many visa numbers DOS has already allocated--for persons applying from abroad as well as those seeking to adjust status from within the United States--for the specific employment preference category during that fiscal quarter. It also depends on whether visa numbers are available within that category for persons from their country of origin, given the 7% per-country ceiling. If a visa is available even with these two constraints, prospective immigrants with approved immigrant petitions can submit an adjustment of status application to USCIS. Although USCIS does not regularly publish reports on the population of foreign nationals with approved immigrant petitions who are waiting to adjust status, one recent report on this pool of applicants is publicly available ( Table 4 ). It indicates that 395,025 approved petitions were pending as of April 20, 2018. Indian nationals, with 306,601 approved petitions (78%), and Chinese nationals, with 67,031 approved petitions (17%), together account for 95% of all petitions in this pool. More than half of these petitions are for the 2 nd employment-based preference category. Figures presented in Table 4 represent only principal immigrants and do not account for derivative immigrants. However, the USCIS report cited in the table also presents FY2016 data on the average number of derivative immigrants receiving LPR status through principal immigrants for each employment-based preference category ( Table 5 ). These "derivative multipliers" presented by USCIS can then be applied to the pending principal petitions to estimate the numbers of derivative immigrants included in the principal immigrant petitions for each preference category. CRS used these multipliers to compute estimated numbers of derivatives that are shown in Table 5 . Summing the total estimated derivative figure (431,842) with the actual principal figure (395,025) yields an estimate of the total number of foreign nationals included in this pool of approved pending immigrant petitions (826,867). The fifth pool of pending employment-based applications includes visa applicants overseas who have had their I-140 immigration petitions approved, have been allocated a numerically limited visa number, and have submitted their application for a visa. Most can expect to receive an interview with a DOS consular official, the last major step in this pathway to LPR status. DOS does not publish statistics on this pool of applications, but in its monthly Visa Bulletin, it presents visa application filing dates in addition to application "cut off" or final action dates. Prospective employment-based immigrants with priority dates on or prior to the filing dates may submit their visa applications and accompanying documentation to DOS. The filing dates, which DOS began publishing in 2015, are intended to have applicants submit their paperwork ahead of time to ensure a more accurate tally of visa numbers available each quarter. A rough estimate of this pool of visa applications submitted to DOS would consist of those whose priority dates fall between the filing dates and the final action dates in the Visa Bulletin. The sixth pool of pending employment-based applications includes foreign nationals (including derivatives) with approved employment-based petitions who had been granted a numerically limited visa number and had filed I-485 ( Application to Register Permanent Residence or Adjust Status ) applications with USCIS to adjust status. Applications in this pool, sometimes referred to as the "I-485 Inventory," fall into two groups. The first group of I-485 adjustment of status applications include those that had received visa numbers prior to March 6, 2017. These were being processed by USCIS's Service Center Operations (SCOPS), and totaled 29,471 as of July 2018 ( Table 6 , Notes). Among this group, almost two-thirds (63%) were filed by 2 nd preference applicants (professionals with advanced degrees or of exceptional ability), and one fourth (26%) by 1 st preference applicants (priority workers). India was the dominant source country for these I-485 applicants with over two-thirds (68%) of the total. The second group of I-485 adjustment of status applications include all those submitted on or after March 6, 2017 which are processed by the USCIS Field Operations Directorate (FOD). Data on the FOD group of I-485 applications are not publicly available. According to USCIS, however, the FOD group is several times larger than the SCOPS group described above. As noted above, prospective immigrants can only file an I-485 application once a visa number is available. For both groups of submitted I-485 applications, therefore, DOS has already allotted visa numbers. As such, these applications represent an administrative processing backlog and not a queue of prospective immigrants waiting for numerically limited visa numbers. USCIS data indicate that the agency approves most I-485 applicants. Thus, these I-485 applicants, who have almost completed the employment-based immigration process, are among the most likely to receive LPR status among the six pools of petitioners and applicants discussed in this section. The discussion above, which described six pools of petitions and applications processed by DOL, USCIS, and DOS across the employment-based LPR process, requires several caveats. First, because the six pools sometimes represent petitions and applications that are summed and presented by agencies at different dates (e.g., November 1, 2017, April 2018), they may not be strictly comparable. Second, figures for petitions at USCIS do not include prospective derivative immigrants, although the latter were estimated for the fourth pool described above (pending approved adjustment of status petitions at USCIS). Third, according to USCIS, some portion of petitions and applications in the fourth pool may be included in other pools discussed because of accounting protocols and processing timing differences. According to the agency, the fourth pool also includes many duplicate or inactive petitions. The six pools present (to the extent permitted by available data) a cross-sectional view of petition and application processing. The first and second pools represent workload queues that reflect relative demand for foreign workers during the fiscal year. The third and fourth pools represent queues of approved pending visa and adjustment of status applications that cannot advance because of the INA's numerical limits and the 7% per-country ceiling. The fifth and sixth pools represent administrative backlogs of applications that have been allocated numerically limited visa numbers and are closest to completion. Proposals to adjust or eliminate the per-country ceiling on employment-based immigration have appeared in legislative proposals in recent Congresses. For example, the Border Security, Economic Opportunity, and Immigration Modernization Act ( S. 744 ), a comprehensive immigration reform bill which passed the Senate in the 113 th Congress, would have eliminated the per-country ceiling for employment-based immigration and raised it for family-based immigration from 7% to 15%. An identical provision was introduced in the 115 th Congress with H.R. 392 (i.e., the "Yoder Amendment" to the Department of Homeland Security Appropriations Act, 2019 ( H.R. 6776 )). Those who favor raising or eliminating the employment-based per-country ceiling argue that the current employment-based immigration system makes prospective employment-based immigrants wait for excessively long periods to acquire LPR status. During these waits, such foreign workers are generally unable to reunite with spouses and children who reside overseas. Others who favor eliminating the per-country ceiling contend that the current system discriminates against some foreign workers based on their country of origin, a characteristic they contend has little bearing on workers' labor market contributions. Such proponents argue that the current system effectively ties immigrant workers to the employers that sponsor them for extended periods and invites potential exploitation. According to this perspective, employers who petition on behalf of prospective employment-based immigrants have disproportionate power over them. Because such employers can withdraw their petitions at will, they discourage foreign workers from negotiating for higher wages and/or improved working conditions. All else being equal, rational employers therefore benefit financially by sponsoring such workers who remain relatively immobile during their extensive waits to receive LPR status. Prospective immigrants who consider leaving their employers face the prospect of effectively forfeiting their pending employment-based immigrant petitions. If they cannot utilize another immigration pathway to remain in the United States, they must return to their home countries. In particular, Indian (and to a lesser extent Chinese and Filipino) nationals sit in much longer queues of pending employment-based petitions submitted to USCIS and visa applications to DOS than their counterparts from other countries. They consequently must wait the longest to obtain LPR status. Those who favor eliminating the per-country cap contend that such circumstances effectively encourage employers to sponsor prospective employment-based immigrants primarily from India. According to this perspective, de facto discrimination results on the basis of origin country, fostered partly by U.S. laws which otherwise prohibit most forms of labor market discrimination. The more that employers follow this hiring approach, the greater the queue of Indian prospective immigrants and the longer the waiting times for acquiring LPR status, creating a self-reinforcing cycle that may limit hiring of prospective employment-based immigrants from other countries. Proponents argue, therefore, that removing the per-country ceiling from employment-based immigrants would "level the playing field" by making immigrants from all countries more equally attractive to employers. If the per-country ceiling is eliminated and the current queue of pending petitions and visas is processed, proponents argue, employers would have no incentive to sponsor employment-based immigrants from any one country over others except based on conventional labor market criteria. As a result, waiting times for prospective employment-based immigrants to receive LPR status would ultimately equalize across countries of origin. From a national interest perspective, many have argued that current circumstances discourage skilled foreign workers from countries such as India from seeking employment and immigration sponsorship in the United States. Prospective immigrants, aware that they could wait for substantial periods of time before actually receiving LPR status, may decide to start their careers and conduct entrepreneurial activities in other countries where the equivalent of LPR status is more quickly obtained. Consequently, firms who wish to attract highly skilled foreign workers may face competitive disadvantages compared to firms based in countries that provide permanent legal status more easily. Some empirical research suggests that long waits for LPR status affects the number of highly trained students in science, technology, engineering, and mathematics (STEM) programs who remain in the United States to work after completing their studies. Opponents of removing the per-country ceiling contend that doing so would substantially reduce country-of-origin diversity and potentially allow a few countries to dominate all permanent employment-based immigration to the United States. They contend that removing the per-country ceiling would advantage Indian and Chinese prospective immigrants who would move more quickly to the head of the queue at the expense of those from all other countries. Arguments against lifting the per-country ceiling often point to the H-1B visa for temporary "professional specialty workers," an employment category generally associated with STEM fields. The H-1B visa represents a frequently used pathway for skilled nonimmigrant (temporary) workers to become employment-based immigrants. Some observers criticize the H-1B visa as exploitative of foreign workers, mostly from India, because once sponsored for employment-based LPR status, workers are unable to change employers, leaving them vulnerable to exploitative practices. They note that Indian nationals dominate H-1B visa recipients with almost three fourths of the total. Many observers are interested in how revising the per-country ceiling would affect future flows of employment-based immigrants. Estimating such impacts are challenging for a number of reasons, including the complex accounting among the six pools of petitions and applications. If Congress eliminated the per-country ceiling for employment-based immigrants, many expect that Indian and Chinese nationals would dominate the flow of new employment-based LPRs for as many years as needed to clear out the accumulated queue of prospective immigrants from those countries. This queue would include those with approved employment-based immigrant petitions who are waiting to file either a visa application with DOS or an adjustment of status application with USCIS (i.e., the third and fourth pools discussed above in " Pools of Prospective Employment-Based LPRs .") As noted above, the "Yoder Amendment," which was introduced during the 115 th Congress and would eliminate the per-country ceiling for all employment-based preference categories, illustrates what kind of impacts might be expected. The amendment would phase out the ceiling over four years. In the first year, a single country could use 85% of all visa numbers in a preference category with the remaining 15% still subject to the 7% per-country ceiling. Thus for the 1 st , 2 nd , and 3 rd preference categories, each of which account for 40,040 visa numbers under the current system, this would amount to 34,034 visa numbers (40,040 x 0.85) for each of the first three preference categories in the first year after enactment. That percentage would increase to 90% for the second and third years (36,036 visa numbers), and reach 100% in the fourth and subsequent years. To illustrate this further, consider the 3 rd employment-based preference category. Data presented above for the third and fourth pools in " Pools of Prospective Employment-Based LPRs " yield an estimated 170,000 principal and derivative immigrants from India, China, and the Philippines who were waiting for LPR status in 2018. Given the parameters of the Yoder Amendment, one could estimate that roughly four to five years would be required to eliminate this queue of prospective 3 rd preference employment-based immigrants. Other outcomes may also result from eliminating the per-country ceiling, apart from reducing certain queues of prospective immigrants more quickly, and removing the perceived employer incentive to choose nationals from these countries over other countries. For example, shorter wait times for LPR status might actually incentivize greater numbers of nationals from India, China, and the Philippines to seek employment-based LPR status. If that were to occur, the reduction in the number of approved petitions pending might be short-lived. In addition, absent a per-country ceiling, a handful of countries could conceivably dominate employment-based immigration, possibly benefitting certain industries that employ foreign workers from those countries, at the expense of foreign workers from other countries and other industries that might employ them. In addition, because the INA grants LPRs the ability to sponsor family members through its family-sponsorship provisions, removing the per-country ceiling would alter, to an unknown extent, the country-of-origin composition of subsequent family-based immigrants acquiring LPR status each year.

Summary:
The Immigration and Nationality Act (INA) specifies a complex set of categories and numerical limits for admitting lawful permanent residents (LPRs) to the United States that includes economic priorities among the admission criteria. These priorities are addressed primarily through the employment-based immigration system, which consists of five preference categories. Each preference category has specific eligibility criteria; numerical limits; and, in some cases, distinct application processes. The INA allocates 140,000 visas annually for all five employment-based LPR categories, roughly 12% of the 1.1 million LPRs admitted in FY2017. The INA further limits each immigrant-sending country to an annual maximum of 7% of all employment-based LPR admissions, known as the per-country ceiling, or "cap." Prospective employment-based immigrants follow two administrative processing trajectories depending on whether they apply from overseas as "new arrivals" seeking LPR status or from within the United States seeking to adjust to LPR status from a temporary status that they currently possess. While some prospective employment-based immigrants can self-petition, most require U.S. employers to petition on their behalf. In both cases, the Department of State (DOS) is responsible for allocating the correct number of employment-based immigrant "visa numbers" or slots, according to numerical limits and the per-country ceiling specified in the INA. This report reviews the employment-based immigration process by examining six pools of pending petitions and applications, representing prospective employment-based immigrants and any accompanying family members at different stages of the LPR process. While four of these pools represent administrative processing queues, two result from the INA's numerical limitations on employment-based immigration and the per-country ceiling. These latter two pools of foreign nationals, who have been approved as employment-based immigrants but must wait for statutorily limited visa numbers, totaled in excess of 900,000 as of mid-2018. Most originate from India, followed by China and the Philippines. Some employers maintain that they continue to need skilled foreign workers to remain internationally competitive and to keep their firms in the United States. Proponents of increasing employment-based immigration levels argue that it is vital for economic growth. Opponents cite the lack of compelling evidence of labor shortages and argue that the presence of foreign workers can negatively impact wages and working conditions in the United States. With this statutory and economic backdrop, the policy option of revising or eliminating the per-country ceiling on employment-based LPRs has been proposed repeatedly in Congress. Some argue that eliminating the per-country ceiling would increase the flow of high-skilled immigrants from countries such as India and China, who are often employed in the U.S. technology sector, without increasing the total annual admission of employment-based LPRs. Currently, nationals from India in particular, and to a lesser extent China and the Philippines, face lengthy queues and inordinately long waits to receive LPR status. Many of those waiting for employment-based LPR status are already employed in the United States on temporary visas, a potentially exploitative situation that some argue incentivizes immigrant-sponsoring employers to continue to recruit foreign nationals primarily from these countries for temporary employment. Others counter that the statutory per-country ceiling restrains the dominance of a handful of employment-based immigrant-sending countries and preserves the diversity of immigrant flows.