Improv Comedy: The History, the Forms and the Schools That Shaped It

Improv comedy is comedy made up in front of you: performers take a suggestion and build scenes, characters and sometimes an entire 30-minute piece with no script at all. It sounds like a party trick. In practice it is a discipline with a seventy-year history, a handful of rival schools and a body of technique that has trained a large share of the funniest people on American television, from Mike Nichols and Elaine May to Tina Fey, Stephen Colbert and Tim Robinson.

This guide covers where improv came from, the forms you will see on stage, the theatres that define the art, how it shaped alternative comedy, and how to start if you want to try it.

What improv actually is

Every improv show begins from nothing, or nearly nothing: a word shouted by the audience, a news story, a personal monologue. The performers have no script, but they are not making it up without rules. They are applying a shared set of habits, practised for years, that let two or ten strangers build something coherent in real time.

The core of those habits is agreement. If your scene partner says you are a dentist, you are a dentist. The famous shorthand is "yes, and": accept what has been offered (yes), then add something to it (and). Most good teachers will tell you that "yes, and" is a starting point rather than a law. What it really teaches is listening, and listening is the skill that separates watchable improv from people taking turns being loud.

Improv comes in two broad styles:

• Short form: quick, self-contained games with a gimmick, such as a scene where every line must be a question or performers who must switch genre on command. This is what most people have seen, thanks to Whose Line Is It Anyway?, which started on British radio and Channel 4 before its long-running American version.
• Long form: a single extended piece, often 20 to 45 minutes, in which scenes, characters and ideas recur and connect. This is the style taught at iO and UCB, and the one most professional comedians mean when they talk about "doing improv."

A short history of improv

1. 1930s–40s

   Viola Spolin's theatre games

   Working in Chicago with the WPA's recreation projects, Viola Spolin developed games to help children and immigrant communities express themselves through play. She built on the work of her teacher Neva Boyd. Her book Improvisation for the Theater (1963) is still the foundational text.

2. 1955

   The Compass Players

   Spolin's son Paul Sills and producer David Shepherd launched the Compass Players near the University of Chicago, the first company to perform improvised and improvisation-built comedy for paying audiences. Mike Nichols, Elaine May, Shelley Berman and Barbara Harris came through it.

3. 1959

   Second City opens

   Sills, Howard Alk and Bernard Sahlins opened The Second City in Chicago. Its revues were developed through improvisation and then set, a model that turned it into the main feeder for Saturday Night Live and later SCTV.

4. 1960s

   Del Close and the Harold

   Del Close, a Compass and Second City veteran, worked with The Committee in San Francisco, where he developed the long form that became known as the Harold.

5. 1970s

   Johnstone, Theatresports and the Groundlings

   In Britain and then Canada, Keith Johnstone developed his own approach, collected in Impro (1979), and invented Theatresports, a competitive format. In Los Angeles, Gary Austin founded the Groundlings in 1974.

6. 1981

   ImprovOlympic

   Charna Halpern founded ImprovOlympic in Chicago and partnered with Del Close, who made it the home of the Harold. The book Truth in Comedy (1994), by Halpern, Close and Kim "Howard" Johnson, spread their method. The theatre later shortened its name to iO.

7. 1987

   The Annoyance

   Mick Napier founded the Annoyance in Chicago, a deliberately scrappier, weirder alternative to the established theatres.

8. 1990s

   Upright Citizens Brigade

   Matt Besser, Amy Poehler, Ian Roberts and Matt Walsh formed UCB in Chicago, moved to New York in the mid-1990s, got a Comedy Central sketch show and opened a theatre that became the centre of New York alternative comedy.

9. 2020s

   Reckoning and reinvention

   In 2020 the pandemic closed theatres, and Second City, iO and UCB all faced public criticism over race, pay and how they treated performers. Second City's longtime owner Andrew Alexander stepped down. Improv moved online, then back to stages, and found new mass audiences through streaming, podcasts and Dropout's improv specials.

The major schools and what each teaches

Improv is tribal, and the tribes are mostly theatres. If you take classes, the school you choose shapes what kind of improviser you become.

Second City (Chicago, Toronto and beyond)

The oldest name in the business. Second City's main stage shows are revues: sketches and songs developed through improvisation, then polished. Its training center teaches improv, sketch writing, musical improv and more. The alumni list is the most famous in comedy: Alan Arkin, Gilda Radner, John Belushi, Bill Murray, Catherine O'Hara, Steve Carell, Stephen Colbert, Tina Fey, Keegan-Michael Key. Our Chicago comedy scene guide covers how it fits into the city.

iO (Chicago)

The church of long form. iO is where Del Close taught the Harold to a generation of performers, many of whom (Amy Poehler, Tina Fey, Adam McKay among them) went on to build modern American comedy. iO's ideal is "group mind": an ensemble so attuned that the piece seems to write itself. The two-person show TJ & Dave, by T.J. Jagodowski and David Pasquesi, is the most-cited example of what patient, honest long form can look like.

Upright Citizens Brigade (New York and Los Angeles)

UCB took Close's teaching and made it more analytical. Its key idea is the game of the scene: find the first unusual thing, then heighten and explore it. The approach is laid out in The Upright Citizens Brigade Comedy Improvisation Manual (2013). UCB's emphasis on clear, repeatable comic patterns made it a pipeline for sketch and TV writers. Its New York theatres closed in 2020; it returned with a new Manhattan venue in 2024. Our UCB Theatre history tells the full story.

The Groundlings (Los Angeles)

The Groundlings is about character. Performers build fully realised people (voices, physicality, point of view) and the school's main company performs a mix of written and improvised sketch. Phil Hartman, Paul Reubens, Lisa Kudrow, Will Ferrell, Maya Rudolph, Kristen Wiig and Melissa McCarthy all came through it, which tells you how well character work translates to SNL and film.

The Annoyance (Chicago)

The Annoyance positioned itself against rules. Mick Napier's book Improvise: Scene from the Inside Out argues that performers should make strong, self-focused choices rather than worrying about agreement and structure. Its stage history includes the long-running musical Co-Ed Prison Sluts, a good indication of the house tone.

Keith Johnstone and the international tradition

Outside the US, Johnstone's influence often outweighs Chicago's. Impro is especially strong on status: the idea that every interaction is a constant negotiation of who is higher or lower, and that shifting status is a reliable engine for scenes. Theatresports and its descendants are played in many countries.

Improv forms you'll see on stage

The Harold

Del Close's signature form. An opening (often a group exploration of the suggestion), then three "beats": in the first, three unrelated scenes; then a group game; then the second beat revisits each scene; then another group game; then a third beat where the threads collide. Done well, it feels like a short story with three plots that turn out to be the same plot.

The Armando

A performer tells a true story inspired by the suggestion, and the ensemble improvises scenes inspired by it, with more monologues along the way. Named after improviser Armando Diaz; UCB's long-running Armando show made it a staple.

The Montage

A loose sequence of scenes with no fixed structure; recurring characters and callbacks emerge naturally. The default form for many house teams.

The Monoscene

One continuous scene in one location for the whole set. Hard, because there are no edits to save you.

The Deconstruction

One opening scene is followed by scenes that explore its themes, characters and implications, before a final return to the original scene.

Short-form games

Structured challenges such as "Freeze," where any performer can stop the action and start a new scene from the frozen physical positions. Common in Theatresports, ComedySportz and touring shows.

Musical improv

Fully improvised songs or whole musicals, with an accompanist following the performers. A specialist skill with its own classes and companies.

The principles that actually matter

Every school has its own vocabulary, but most good improv rests on a few ideas:

• Listen more than you talk. The funniest line in a scene is usually a response to something your partner did, not something you prepared.
• Make your partner look good. The ensemble ethic, from Spolin onward, is that support beats showing off. Scenes die when performers compete.
• Establish the basics fast. Who are we, where are we, what is our relationship? Clear "base reality" lets an audience notice when something strange happens.
• Find the game, then heighten. UCB's version: identify what is unusual and do it again, bigger, with a reason. This is why improv-trained writers tend to write tight sketches.
• Commit to the truth of the moment. Close argued that honest reactions were funnier than jokes. Audiences laugh at recognition, not at someone trying to be clever.
• Be specific. "A sandwich" is nothing; "the egg salad my mother made the day Dad left" is a scene.

Improv and alternative comedy

The relationship between improv and alternative comedy is closer than the two scenes sometimes admit. In New York in the late 1990s and 2000s, the UCB Theatre and the stand-up rooms around it shared audiences, performers and a taste for the strange. In Los Angeles, the same performers moved between UCB, the Groundlings and alt stand-up nights.

Plenty of landmark alternative comedy is improvised or improv-built:

• Comedy Bang! Bang!, the podcast and later IFC series, runs on improvised character guests, many of them UCB veterans.
• Curb Your Enthusiasm and Christopher Guest's films (Waiting for Guffman, Best in Show) work from detailed outlines with improvised dialogue.
• I Think You Should Leave is scripted, but Tim Robinson's Second City background shows in its total commitment to a single escalating game.
• Netflix's Middleditch & Schwartz (2020) put two-person long form on a major streamer, and Dropout's improv shows have since found a large online audience.

Improv's ensemble habits also shaped how alt comedy is written. Our piece on collaborative comedy looks at why so many great double acts and writing rooms trace back to an improv stage.

Safety, consent and the 2020 reckoning

Improv's culture of total agreement has a dark side. When "yes, and" is treated as an absolute, performers can feel pressured to accept physical contact, sexual content or scenes built on someone's identity. In 2020, many performers spoke publicly about racism, harassment and unpaid labour at major improv institutions, and the larger theatres made leadership and policy changes in response.

Good teachers now say clearly that agreement applies to the fiction, not to your body or boundaries. Many theatres have codes of conduct, and many performers use simple pre-show check-ins. If a class or team treats discomfort as a failure to "yes, and," that is a red flag, not a training method.

How to start doing improv

1. Watch first. Go to a few shows at your local improv theatre, including house teams and student shows. You'll learn more about the house style in two nights than from any website.
2. Take a level one class. Most theatres offer an introductory course of several weeks. No experience is needed. Look at who teaches it and what the curriculum emphasises (game, character, group mind).
3. Join or form a practice group. Classes give you rules; practice groups (often called "jams" or "indie teams") give you stage time.
4. Read the books. Spolin's Improvisation for the Theater, Johnstone's Impro, Truth in Comedy and the UCB manual cover the major philosophies. Read at least two that disagree with each other.
5. Do it a lot. Improv is a performance skill. Reps matter more than theory.

Improv rarely makes anyone rich, and most improvisers never perform outside their local theatre. But the skills (listening, committing, building on someone else's idea) explain why so much of the comedy you love was written by people who started by making things up.

Frequently asked questions

What is improv comedy?

Improv (improvisational comedy) is comedy performed without a script: performers build scenes, characters and stories on the spot, usually from an audience suggestion. It comes in short-form games, as on Whose Line Is It Anyway?, and long-form pieces such as the Harold.

Who invented improv?

No single person, but modern improv descends from Viola Spolin's theatre games, developed from the 1930s onward. Her son Paul Sills co-founded the Compass Players (1955) and Second City (1959), and Del Close and Keith Johnstone later shaped long-form and Theatresports respectively.

When was iO (ImprovOlympic) founded?

ImprovOlympic was founded in Chicago in 1981 by Charna Halpern, and Del Close soon became its central teacher. It shortened its name to iO in the early 2000s.

What is the Harold in improv?

The Harold is a long-form structure developed by Del Close: an opening inspired by a suggestion, then three rounds of scenes with group games in between, where separate storylines gradually connect. It became the signature form of iO and UCB.

What is the difference between Second City, UCB and the Groundlings?

Second City is best known for revues written through improvisation; UCB teaches long-form improv built around finding the 'game' of a scene; the Groundlings in Los Angeles focuses on character work and sketch. Many performers train at more than one.

Do I need acting experience to take an improv class?

No. Level one classes at most theatres assume no experience. They teach listening, agreement and scene-building through games, and many students take them for confidence rather than a career.