One way to understand the Unanimous Consent and Hold procedure is to imagine sitting in a restaurant with a large group of friends. When the bill comes one of the party suggest the groups all pay the same amount regardless of what they have ordered. This, it is suggested will make paying the bill so much quicker and although some people will pay a little less than they should and some will pay a little more everyone will benefit from the ease of not having to calculate every one's bill separately. This can only be done if everyone agrees. (Unanimous Consent) however, if one person objects (Hold) they will all have to revert to individual bills.

In the case of appointments and promotion in the military or if a bill in Congress has many parts the option to break the bill down may not be an option because of limited legislative time so the hold becomes a defacto veto.

Unanimous consent agreements bring order and structure to floor business and expedite the course of legislation. They can be as simple as a request to dispense with a quorum call or as complicated as a binding contract resulting from prolonged and often spirited debate. Senators have been conducting routine business by unanimous consensus since 1789, but the more formal UC agreement dates to the 1840s when Senator William Allen of Ohio sought a method to end debate.

On March 24, 1846, Senator Allen expressed his desire “that there should be some day fixed, by a general understanding,” to bring to close the debate on the Oregon Treaty. After all, for nearly four months, the Senate had been debating this treaty involving a long-standing boundary dispute with Great Britain. Settlement of the treaty would pave the way for the new state of Oregon.

Unfortunately for Allen and his allies, there was no mechanism in place to force a vote, or even to encourage a vote. Cloture, as we know it today, was not established until 1917. As Allen explained, the Senate had not adopted the House’s practice of calling the “previous question,” nor was it “the habit of the Senate to pass a resolution to take a subject out of discussion.” Allen emphasized, however, that the Senate did have a practice of facilitating votes by “a conversational understanding.”

The Senate responded to Allen’s suggestion in a typically polite but pointed manner. I oppose “the adoption of any rule or practice by which debate should be stifled,” protested Tennessee senator Spencer Jarnagin. Gentlemen can “determine for themselves” when proper action should be taken. And so, the debate over the Oregon Treaty continued.

On April 13, 1846, Allen again took the floor. A vote on the Oregon question was inevitable, he argued, so why not agree “to the exact day on which the Senate would proceed to vote.” Such action would be acceptable, argued Kentucky’s James Morehead, “provided it was not to be regarded as establishing a precedent.” But it did set a precedent. Senators reached a consensus and agreed unanimously to end debate and call a vote. In June the Senate approved the treaty resolutions, a territory was established, and in 1859 Oregon became our 33rd state. Scholars believe this is the first example of the Senate adopting a formal UC agreement.

Before long, such pacts were common, but into the 20th century they remained just “a gentlemen’s agreement.” As one presiding officer complained, they could be “violated with impunity” by any senator. Consequently, in January of 1914, the Senate adopted a new rule stating that unanimous consent agreements “shall operate as the order of the Senate” and can be altered only by another UC agreement

By the 1950s UC agreements were a routine but limited procedural tool—and then Lyndon Johnson became leader. Truly understanding the potential of this procedural device, LBJ revamped UC agreements to regulate the entire legislative process—to manage debate, to limit amendments, to schedule a vote, and to strengthen the force of his own majority leadership.

In the United States Senate, a hold is a parliamentary procedure permitted by the Standing Rules of the United States Senate which allows one or more Senators to prevent a motion to proceed with consideration of a certain manner from reaching a vote on the Senate floor, as no motion may be brought for consideration on the Senate floor without unanimous consent (unless cloture is invoked on the said motion).

If the Senator provides notice privately to their party leadership of their intent (and the party leadership agrees), then the hold is known as a secret or anonymous hold. If the Senator objects on the Senate floor or the hold is publicly revealed, then the hold is more generally known as a Senatorial hold.

In the United States Senate, a hold is a parliamentary procedure permitted by the Standing Rules of the United States Senate which allows one or more Senators to prevent a motion to proceed with consideration of a certain manner from reaching a vote on the Senate floor, as no motion may be brought for consideration on the Senate floor without unanimous consent (unless cloture is invoked on the said motion).

If the Senator provides notice privately to their party leadership of their intent (and the party leadership agrees), then the hold is known as a secret or anonymous hold. If the Senator objects on the Senate floor or the hold is publicly revealed, then the hold is more generally known as a Senatorial hold.

In the Senate, a hold on a nomination is a communication to the majority or minority leader that a Senator would object to approving the nomination by unanimous consent. When Senators inform their leader that they would object to approving a category of nominations by unanimous consent, such as all nominations to a particular government agency, they are said to be placing a blanket hold on those nominations. Unanimous consent is not necessary to approve a nomination in the Senate, but unanimous consent facilitates approving a nomination quickly. The President sends the Senate thousands of nominations each year, a majority of which are military promotions and appointments. The Senate routinely considers and approves most of them in large groups (en bloc) by unanimous consent. Absent unanimous consent, the Senate must consider and vote on each nomination separately (that is, on each individual nominated to each position). As a result, nominations subject to a blanket hold may have their consideration delayed or prevented due to the amount of floor time it would take to consider them individually. Approving a nomination by unanimous consent requires that a Senator ask, during a session of the Senate, for that action to occur. Such requests are usually made by the majority leader (or his designee), and the Presiding Officer responds by inquiring if any Senator objects to the unanimous consent request. If no Senator objects, then the nomination or nominations are approved—more formally, the nominations are said to be confirmed by the Senate. In practice, the majority leader does not ask unanimous consent to confirm nominations without first communicating with the minority leader and all other Senators to determine if any Senator would object. If the majority leader learns any Senator would object, he usually does not ask unanimous consent on the floor and may try to address the concerns of the Senator. If a consent request has not been cleared in advance, a Senator opposed to the request must formally object on the floor to block the action.