This article does not cite any references or sources. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. (December 2009)

Steve Jobs is a typical keynote speaker. Here he is pictured during Macworld 2008.

A keynote in literature, music or public speaking is the principal underlying theme. In corporate or commercial settings, greater importance is attached to the delivery of a keynote speech or keynote address. The keynote will lay down the framework for the following programme of events or convention agenda; frequently the role of keynote speaker will also include the role of convention moderator. It will also flag up a larger idea — a literary story, an individual musical piece or event.

At political or industrial conventions and expositions and at academic conferences, the keynote address or keynote speech is delivered to set the underlying tone and summarize the core message or most important revelation of the event. Some of the more famous keynote speeches in the United States are those at the party conventions during Democratic and Republican presidential campaigns. Keynote speakers at these events have often gained nationwide fame (or notoriety); for example, Barack Obama at the 2004 Democratic National Convention, and have occasionally influenced the course of the election. Similar speeches are given at political conventions and party meetings throughout the world.

Keynote speeches are also given at the graduation and commencement ceremonies of colleges, universities, and major high schools, usually by accomplished academics or celebrities invited by the student body.

Keynote speakers are often selected to raise interest in a particular event, such as a conference or large meeting sponsored by a corporation or association, and draw attendees to attend that program. Selecting a keynote speaker who is well known for his or her expertise in a particular field, or who has wide name recognition due to other accomplishments, will probably raise enthusiasm among prospective attendees for a meeting or conference.

Typically a keynote presenter speaks for anywhere from 45 to 60 minutes. Although many speakers are honored to attend the event and may earn publicity in their own right for their presentation, for larger or corporate sponosored events, an honorarium or speakers fee is generally paid.

The term Key Note come from the practice of a cappella, often Barbershop singers, playing a note before singing. The note played determines that key in which the song will be performed, thus the term Key Note.