1. Amending The Constitution Requires Two Steps
A change is proposed.
It then becomes an official
proposal by a two thirds vote
of Congress
Three- Fourths of the states
must then ratify the
proposed amendment.
It can also be done if two- thirds
of the states vote for a national
constitutional convention.
Or a special state convention
can be called. (only the 21st
has used this method).

2. Informal Amendment Process
Although the Const. has only been changed 27 times there have been
a few different changes in the way the Gov. operates. Many of these changes
have come about through the Informal Amendment Process and does not
involve the changing of the Cont.’s wording. These Informal changes may
occur in the following ways:
Legislative Actions:
Congress has passed a number of acts whose meaning is to bring
clarity to the Const.
EX: under Article III Congress was given the power to create
lower courts (Judiciary Act of 1789), Voting Rights Act of 1965

3. Informal Amendment Process
Executive Actions:
The manner in which presidents use their powers can create
informal amendments and expand presidential authority
Ex: The use of executive agreements rather than treaties allows
the president to bypass the Senate
Judicial Interpretation/Judicial review:
The people who serve as judges and the times in
which they serve affect how courts interpret laws
EX: the concept of judicial review resulted from
Marbury v. Madison (1803) is not mentioned
in the Const.

4. Informal Amendment Process
Custom and Usage:
Traditions which have been incorporated into the political system
and which have lasted over time have changed the meaning
of the Constitution.
Ex: Senatorial Courtesy, no 3rd term, Filibuster