Amateur Cast

"They don't use actors in Italian pictures -- they use people."

—Jerry Biffle (Phil Silvers), Top Banana

When a professional film director decides to use a bunch of untrained amateurs to act out a fictional story (that is, not a Documentary). Differs from Non-Actor Vehicle in that the non-actors tend to be unknown to fame.

Examples of Amateur Cast include:

Film

As the page quote suggests, almost any movie from the Italian neorealism period:
- Bicycle Thieves
Raising Victor Vargas, which makes good use of Real Life Relatives to play related characters.
The Afghan movie Osama did this.
Werner Herzog is known to do this, with Stroszek being the best example. Bruno S. made only two films, both with Herzog, and Eva Mattes was the only professional actress in it — everyone else was just someone whom Herzog saw during filming and wanted to use.
Peter Hall's 1974 British film Akenfield used entirely non-union amateur actors (and apparently cameramen, too, by the look of it).
To Kill a Mockingbird did this with the parts for the children, which were filled by local kids near the shooting spot. None of them went on to have a career as a normal actor.
Many of the actors in A Serious Man.
Most of the Harry Potter kids had never acted professionally at the time of the first movie, in contrast to the All-Star Cast of adults. However, the series lasted so long that they ceased to be amateurs simply through the process of making it.
Martin Scorsese cast his Dalai Lama Biopic Kundun mostly with actual Tibetan Buddhist monks.
The Kite Runner did this, at least with the Afghan actors, using actual Afghan people.
Most of the cast of The Commitments (at least the actors who portrayed the band) were mostly unknowns selected for their musical talent.
The star of District 9, Sharlto Copley, was hired because he just happened to be hanging out where the director was filming footage for the effects test.
French director Robert Bresson used to do this.
The Swedish movie Show Me Love had a largely inexperienced cast.
In the film version of I Miss You I Miss You nearly all of the teenage characters were played by amateurs.
The punks in Suburbia are, in fact, played by real punks.
Steven Soderbergh made Bubble without any professional actors. Lead actress Debbie Doebereiner, for instance, was discovered working at a KFC drive-thru.

Live Action Television

The original cast of Red Dwarf had all appeared on TV and/or film before, but none of them were "proper actors": Chris Barrie was an impressionist & voice actor, Craig Charles was a poet, Danny John-Jules was a dancer and Norman Lovett was a stand-up comedian. Likewise, Hattie Hayridge was also a stand-up comedian before joining the cast in Series III; however, Robert Llewellyn and Chloe Annett (who joined the cast in Series III and VII respectively) were both "legit" actors.
The early 90's cast of Saturday Night Live was made up almost entirely of standup comedians (David Spade, Adam Sandler, etc.) instead of the improv actors the series had relied on. Although Vindicated by History, the ratings were so low that the show was almost cancelled. This is often blamed on the cast concentrating on characters from their standup instead of doing ensemble work.

Video Games

The cast in Command & Conquer: Tiberian Dawn consisted of Westwood developers and staff members due to budget constraints, which gave the series a reputation for having campy FMV cutscenes; the only Westwood employee to have any extensive theatrical experience was Joseph D. Kucan, who played the role of Kane.
For the original Max Payne, Remedy employees posed as characters for the game's graphic novel-style panels, with Sam Lake standing in for Payne. Lake even had his mother play the role of Nicole Horne.