Conference committees can be created by the House and Senate after each chamber has disagreed to the position of the other. Conference committees develop and present compromise legislation, in the form of a conference report, for approval in each chamber. The difference between amendments between the houses and a conference committee is not necessarily in the way a policy compromise is reached but in the formal parliamentary steps taken after the principal negotiators have agreed to a compromise. Throughout the report, the phrase "amendment exchange" is sometimes used as an alternative to the longer but formal name of "amendments between the houses." The second step, agreeing to the same legislative language, is generally more challenging. The chambers can resolve their differences over the text either (1) through an amendment exchange, when the chambers shuttle the bill and amendments back and forth between them proposing alternatives in hopes that both houses will eventually agree on the same language; or (2) through a conference committee, a panel of Members from each chamber that meets to resolve the differences between the bill and the amendment(s) proposed by the second-acting chamber. Most of the time, the majority leader requests that the Presiding Officer lay the amendment(s) before the Senate in the following way:
Senator: Mr. President, I ask the Chair to lay before the Senate a message from the House on the bill S.____, with the amendment(s) of the House thereto. The limitation on the number of rounds of amendment still applies in a situation in which the Senate must dispose of multiple House amendments. The prohibition against amending text both chambers have agreed to can complicate changing long titles of bills in the Senate; if the House and Senate both passed a bill and agreed to the same long title, it would take unanimous consent in the Senate to agree to a House amendment to the title. In addition, any motion to concur with an amendment is itself subject to amendment. In recent Congresses, the majority leader has typically offered three motions to fill this tree: (1) the motion to concur in the House amendment; (2) the motion to concur in the House amendment with an amendment (a motion that would be in order with the straight motion to concur pending); and (3) a perfecting amendment to the amendment proposed in the motion to concur. House amendments are called up without debate, and if the majority leader then "fills the tree," amendments are precluded (at least temporarily). Bicameral meetings and conversations among Senators, Representatives, and staff from the relevant committees of jurisdiction can be substantively similar regardless of whether the resulting compromise is embodied in an amendment between the houses or a conference report. Some requirements under the rules can apply to amendment exchange procedures but not to conference reports. Typically, the House disposes of Senate amendments through one of the expedited processes described below: a special rule reported by the Committee on Rules, a motion to suspend the rules, or by unanimous consent. Motion to Recommit Usually Not Allowed

In contrast to the initial consideration of a bill or joint resolution under the terms of a special rule, consideration of Senate amendments is unlikely to include an opportunity for a Member of the minority party to offer a motion to recommit (or to commit, if the matter had not already been before the committee). As discussed at length above, if the House acts on a Senate amendment, instead of acting on a bill or joint resolution that has not yet passed the House, then (1) the motion to recommit is less likely to be in order, and (2) there will not necessarily be a single vote in relation to the Senate amendment, because the House proposal might be considered as separate amendments to the Senate amendment.
The House and Senate must agree to the same measure with the same legislative language before a bill can be presented to the President. To resolve differences between House and Senate versions of legislation, Congress might appoint a conference committee to negotiate a compromise that is then reported to each chamber for consideration. Alternatively, Congress might use the process of amendment exchange. In this process, each chamber acts on the legislation in turn, shuttling the measure back and forth, sometimes proposing alternatives in the form of amendments, until both chambers have agreed to the same text.
The difference between a conference committee and an amendment exchange is not necessarily in the way a policy compromise is reached but in the formal parliamentary steps taken after the principal negotiators have agreed to a compromise. After each chamber has passed its version of the legislation—or in some cases even before that stage—Senators, Representatives, and staff from the relevant committees of jurisdiction engage in policy discussions in an effort to craft compromise legislation that can pass both chambers. These informal meetings and conversations are sometimes referred to colloquially as "pre-conference," although they need not be followed by the convening of a formal conference committee. The phrase is applied generally to final-stage efforts to prepare legislation for passage in both the House and the Senate.
The decision to use the amendment exchange route has procedural implications. Amendments between the houses are not subject to the same procedures as conference reports. For example, some of the limitations on the content of conference committee reports do not apply to amendment exchange. Furthermore, amendment exchange provides alternative opportunities to structure decisions, because the policy compromise can be voted on as separate amendments between the houses instead of as a single legislative package. In addition, in the Senate, House amendments are privileged, and therefore their consideration typically begins immediately after the majority leader asks the Presiding Officer to lay them before the Senate. In contrast, to begin consideration of a bill or resolution, the majority leader must either obtain unanimous consent or make a motion to proceed to the measure, which is debatable in most circumstances. Furthermore, in the House, consideration of Senate amendments is unlikely to include an opportunity for a Member of the minority party to offer a motion to recommit, an opportunity that is generally assured on initial consideration of a bill or joint resolution.
In an amendment exchange, the formal actions the chambers generally take on amendments from the other chamber are (1) to concur, (2) to concur with an amendment, or (3) to disagree. There is a limit to the number of times each house can propose amendment(s) and send the measure back to the other house, but in both chambers the limitation can be waived. In the contemporary House, Senate amendments are typically disposed of through a special rule reported by the Committee on Rules, a motion to suspend the rules, or by unanimous consent. In the Senate, consideration of House amendments has the potential to become procedurally complex, particularly when the Senate must dispose of multiple House amendments. Because House amendments, unlike conference reports, are subject to amendment, the Senate majority leader might offer a motion to dispose of the House amendment and then "fill the tree" to temporarily prevent any Senator from proposing an alternative method of acting on the House amendment.