No matter how good a job you've done creating your bylaws, sooner or later you'll need to change something. Robert's Rules encourages creating bylaws that can't be too easily amended, but amending them isn't so difficult that you can't consider and make changes within a reasonable time when necessary.
Setting the conditions for amending your bylaws
In amending a previously adopted bylaw, make sure that the rights of all members continue to be protected. The surest way to provide this protection is to prevent bylaws from being changed without first giving every member an opportunity to weigh in on a change. And bylaws should never be changed as long as a minority greater than one-third disagrees with the proposal.
Always specify in your bylaws the exact requirements for their amendment. According to Robert's Rules, you should, at the very least, require a two-thirds vote and previous notice to make any change at all in your bylaws.
Giving notice of bylaw amendments
Amending bylaws essentially changes the contract you've made with your fellow members about how your organization operates, so you need to be really technical and precise. The proper notice for a bylaw amendment contains three fundamental components:
The proposed amendment, precisely worded
The current bylaw
The bylaw as it will read if the amendment is adopted
Additionally, the notice should include the proposers' names and their rationale for offering the amendment. It may also include other information such as whether a committee or board endorses or opposes the amendment.
Handling a motion to amend bylaws
When the time comes to deal with the amendment on the floor, you're handling a special application of the motion to Amend Something Previously Adopted. The bylaw amendment is subject to all the rules for that motion except for the following:
The provisions for amendment contained in your bylaws determine the requirements for previous notice and the vote required to adopt a bylaws amendment. But if your bylaws have no provisions for their amendment, the requirement is a two-thirds vote with previous notice, or without notice, a majority of the entire membership.
Primary and secondary amendments to your proposed bylaw amendment can't exceed the scope of the notice. So you can't send notice of a change to raise the dues by $10, then amend the proposal to up the dues by more than $10. You can amend the proposal to increase the dues only $8, because an $8 increase is within the scope of notice.
After you've adopted an amendment, that's it. You can't reconsider the vote. (But if the amendment fails, you can reconsider that vote.)
The rule against considering essentially the same question twice in a meeting doesn't apply when you're amending bylaws. Members may offer different ideas on how to handle things, and all bylaw amendments included in the notice are eligible for consideration.
Even though other amendments addressing the same issue have to be considered if proper notice has been given, you can't get around the possibility that after you adopt a particular bylaw amendment, other proposals may become moot because any change in the bylaws may make a yet-to-be-considered amendment impossible to enact.
Amending specific articles, sections, or subsections of your bylaws
When you're amending parts of your bylaws, you propose the amendment as a main motion and specify one of the same processes you would for any amendment. The processes of the motion to amend are
Strike out words, sentences, or paragraphs
Insert (or add) words, sentences, or paragraphs
Strike out and insert (or substitute) words, sentences, or paragraphs
Tackling a full revision of your bylaws
A revision to bylaws is an extensive rewrite that often makes fundamental changes in the structure of the organization. By considering a revision of your bylaws, you're proposing to substitute a new set of bylaws for the existing ones. Therefore, the rules regarding scope of notice that limit primary and secondary amendments don't apply. Your group is free to amend anything in the proposed revision before it's adopted, as if the bylaws were being considered and adopted for the first time.
Recording the results of the vote
Bylaw amendments (requiring a two-thirds vote) are handled as a rising vote unless the amendments are adopted by unanimous consent. However, because of the importance of bylaws and the impact of their amendment, unless the vote is practically unanimous, the best and fairest procedure is to count the vote and record the result in the minutes.