Since a 1989 constitutional reform, Costa Rica's judicial branch has undergone a major transformation; it abandoned traditional deference toward the popular branches of government and became one of the most active and politically significant courts in the Americas. This newly energized court has transformed Costa Rican politics through its aggressive exercise of a horizontal accountability function that has limited the actions of the other branches of government, and it has demonstrated a willingness and ability to support and enforce a greatly expanded range of individual rights. In terms of the book's framework, illustrated in Table 2.1, Costa Rica's pre-1989 superior court was firmly located in the upper left-hand quadrant, offering virtually no rights protection and imposing few limitations on the actions of the popular branches of government. The reformed court is clearly situated in the bottom right-hand quadrant, actively employing an accountability function and protecting individual rights to a greater extent than any other court in the Americas, with the possible exception of the Colombian Constitutional Court.