Bicameralism

[Page 58]Bicameralism is a political system in which the legislative branch is composed of two chambers, usually known as the first and second chambers (or lower and upper houses). More than one third of all national parliaments are bicameral. It is a system that is common in both presidential and parliamentary democracies, and it is particularly prevalent in federal countries. Where second chambers exist, they vary greatly in terms of powers and composition, and these two factors together shape the impact that they have on legislation. This entry provides an overview of the main characteristics and forms of bicameralism and concludes by discussing the main arguments regarding its merits.