An experiment performed at Stanford University to measure the connection between the development of self-restraint at young age and success later in life.

The subjects were 4-year-old children chosen from the university's attached kindergarten.

In the experiment, the children were promised a second marshmallow on the condition that they kept from eating the one on the table for 15 minutes. The children were placed in a room with nothing but the table and a chair, and their self-restraint observed.