MIT STEP Lab Presents

Tragedy of the Commons (PSim)

Tragedy of the Commons (ToC) is a Psim game.


Tragedy of the Commons (ToC) is a Psim game about cooperation, competition and management of shared resources.  The game challenges players to be “successful fishers”.  They do this by buying boats and going “fishing” in each round.  There are a finite number of fishing spots around the room, and (as it turns out) a limited amount of fish.  Players must figure out how to manage the shared resource and define what it means to be successful.

This game is based on a well known economic problem (see for example and

This game can be useful in a number of contexts.  It is a game about sustainability, modeling, economics, and cooperation.  It involves elements of population biology, but can also be used in a social sciences context.

Different groups may come up with quite different solutions, which makes this an interesting game to run multiple times.



The Tragedy of the Commons PSim is now publicly available.  This version is a public beta.  You are free to sign up and use the game.  Right now the primary way of accessing the game is a web client.  There are efforts for native clients but they are out of date.  Teachers will need a google account to sign in.  Students sign in anonymously and only need a device (preferably or a phone or tablet) running Chrome on Android or Safari on iOS.

Tragedy of the Commons Documentation

Tragedy of the Commons Supplemental Remote Play Documentation

Tragedy of the Commons Slides

Game Site:

link to Tragedy of the Commons student client (teacher must use the website) for


iOS –

Android –

Project Specifics


Recommended for ages 10 and older

Content Area

Biology, Social Sciences, Economics


iOS and Android mobile devices

Project Contact

psims [at] mit [dot] edu