Under the Appointments Clause of the Constitution, the President and the Senate share responsibility for making appointments to the Supreme Court, as well as to various lower courts in the federal judiciary. While it is the President who nominates persons to fill federal judgeships, the appointment of each nominee also requires Senate confirmation. Historically, the vast majority of appointments to judgeships in federal courts other than the Supreme Court have typically not engendered much public disagreement between the President and the Senate and between the parties within the Senate. Debate in the Senate over particular lower court nominees, or over the lower court appointment process, was uncommon, with controversy arising over nominees only on rare occasions. Most such nominations typically were both reported out of committee and confirmed by the Senate without any recorded opposition. In recent decades, however, appointments to two kinds of lower federal courts—the U.S. district courts and the U.S. circuit courts of appeals—have often been the focus of heightened Senate interest and debate, as has the process itself for appointing judges to these courts. Given congressional interest in the subject, this report is intended to provide readers with a basic overview of the appointment process for U.S. circuit and district court judges. Accordingly, the report, following a brief background section, describes, in successive parts, the three primary phases of the appointment process, namely the selection of judicial nominees by the President, including the key role often played by home state Senators in recommending judicial candidates to the President; the role of the Senate Judiciary Committee in considering and deciding whether to approve and report out the President's judicial nominations to the Senate; and the Senate's floor consideration and confirmation of judicial nominations, through use of either its unanimous consent process or its cloture process. The report then discusses the final appointment steps for nominees after Senate confirmation, including receipt of commissions signed by the President and the taking of their oaths of office, as well as various possible outcomes for nominees whose nominations are not confirmed, including the possibility of their being re-nominated. The report's exclusive focus, it should be emphasized, is the process of appointment of U.S. circuit and district court judges through presidential nomination and Senate confirmation . This has been, historically as well as in contemporary times, the process by which the vast majority of circuit and district court judges have been appointed. Not analyzed in this report are judicial appointments that occur on rare occasions when a President exercises his constitutional power to make "recess appointments," a process under which an individual can temporarily take office without Senate confirmation. The U.S. district courts are the trial courts of general federal jurisdiction, while the U.S. circuit courts of appeals are the intermediate appellate courts that generally consider appeals in cases originally decided by the district courts. With the Supreme Court deciding fewer than 100 cases per term, the district and circuit courts, one scholar has written, "today serve as the final arbiter of more than 99 percent of all federal court litigation," with "important policy ... being made every day in the lower federal courts." Ruling on a wide range of issues, the lower courts, and the persons selected to serve as judges on those courts, arguably have become of much more interest and concern to Congress in recent decades than they were historically. As congressional interest in the lower federal courts has heightened, the judicial appointment process in turn has often been at the center of Senate debate. In committee and on the Senate floor, Senators periodically have debated over the standards to use in evaluating judicial nominees; over whether certain nominees, if confirmed, would be impartial judges or bring with them ideological agendas or other disqualifying biases; or over how promptly or deliberately to act on judicial nominations. The judicial confirmation process in the Senate also is longer than it was historically. During the three most recent presidencies (of Bill Clinton, George W. Bush, and Barack Obama), the Senate has, on average, taken much more time to confirm district and circuit court nominees than it did previously—with average times from date of first nomination to confirmation no longer measured in weeks but in multi-month or half-year periods. Perhaps indicative of a more contentious process, the Senate in recent years has been confirming fewer district and circuit nominees by unanimous consent or voice vote than previously, increasingly voting instead by roll call, often with some, and occasionally with a substantial minority of, Senators casting "nay" votes. Periodically during recent presidencies, the Senate has been divided over when or whether to hold up-or-down confirmation votes. Illustrative of such division have been occasions where motions filed by Senators of the President's party to close debate on particular nominations have, in roll call votes, been opposed, and sometimes defeated, by a substantial number of "nay" votes cast by Senators of the other party. Frequently, debate over judicial nominations also has centered on the general pace at which the Senate should process the nominations. In a recurring pattern of this debate over recent years, Senators of the President's party, on the one hand, have accused the other party of generally engaging in "obstructionism" or tactics designed to delay or block committee or full Senate action on particular or even relatively large numbers of judicial nominations. Senators of the opposite party, on the other hand, have denied engaging in delaying tactics against judicial nominations, while asserting a Senate duty, under the Constitution's Appointments Clause, to deliberately review the qualifications of judicial nominees rather than to rush or "rubber stamp" the processing of their nominations. Often, in this debate, a related Senate concern has been the number of district or circuit judgeships vacant at that particular time. Senators, along party lines, have differed over whether judicial vacancy levels, when relatively high, were primarily due to delays by the President in making judicial nominations, or to delays by the Senate in confirming them. Recent frustrations over the judicial appointment process led to a bipartisan agreement reached on January 25, 2013, early in the first session of the 113 th Congress. That day, by a 78-16 vote approving S.Res. 15 , the Senate established a standing order of the Senate which could accelerate the consideration of nominations, including those to the district courts. The standing order, applicable only in the 113 th Congress, significantly reduced (from 30 to 2 hours) the maximum time for consideration of district court nominations after at least three-fifths of the Senate had agreed that debate on the nominations should be brought to a close. The order excluded circuit court nominations (as well as nominations to the Supreme Court, the U.S. Court of International Trade, and major executive branch positions), for which the length of "post-cloture" consideration, under Senate rules, continued to be 30 hours. Throughout the rest of 2013, however, the Senate again found itself periodically divided, along party lines, over judicial nominations. At issue was how quickly the Senate should act on lower court nominations in general, and whether or when various circuit court nominations pending on the Senate's Executive Calendar should receive confirmation votes. Late in the session, confirmation votes on three circuit court nominations were prevented when motions to close Senate debate on them received only simple majority votes in favor, rather than the three-fifths supermajority then required under Senate rules to close debate. These episodes (along with a simple Senate majority unable again, under similar circumstances, to close debate on an executive branch nomination) set the stage for the Senate's majority leader, shortly thereafter, to put before that body the following issue: Whether, as the majority leader proposed, the Senate should change its procedure to require only a simple majority vote in order to close debate on nominations—thereby more easily reaching confirmation votes, including those on circuit and district court nominations. The proposed procedural change was referred to by some Senate Members, as well as by outside observers and news media reports, as the "nuclear option." On November 21, 2013, the proposed change in procedure was considered by the Senate. By a vote of 52-48, it overturned a ruling of the chair and set a precedent that lowered the vote threshold required by the Senate for "invoking cloture" (closing debate) on most presidential nominations. Specifically, the Senate reinterpreted the provisions of Senate Rule XXII to require only a simple majority of those voting, rather than three-fifths of the full Senate, to close debate on all presidential nominations except those to the Supreme Court. The November 21, 2013, reinterpretation of its cloture rule ushered in a significant change in the way that the Senate thereafter processed circuit and district court nominations. For the rest of the 113 th Congress, until the day of its final adjournment almost 13 months later, cloture motions, rather than unanimous consent (UC) agreements, were the invariable procedural tool used in the Senate to reach confirmation votes on these nominations. Specifically, from November 21, 2013, through December 15, 2014, the process for every confirmed circuit or district court nomination involved the filing of a cloture motion, with the Senate then voting to invoke cloture. With a vote threshold needed to close debate lower during this period than it was previously, every motion filed to close Senate debate on a circuit or district court nomination succeeded, followed in turn by each nomination receiving Senate confirmation. During this period, no confirmations of circuit or district court nominations were reached through the unanimous consent process. The Senate, however, would eventually return to using unanimous consent agreements to reach confirmation votes on judicial nominations. On December 16, 2014, the day of the final adjournment of the 113 th Congress, the Senate reverted, for the first time in more than a year, to using a UC agreement, rather than the cloture process, to reach confirmation votes on district court nominations. Regular reliance on UC agreements to process judicial nominations returned in the 114 th Congress, coinciding with a change in party control of the Senate.