In 1910 he worked at the Psychological Institute of Frankfurts University. There he became interested in perception. Together with two younger assistants, Wolfgang Köhler and Kurt Koffka he studied the effect of moving pictures a toy stroboscope generates. In 1912 he published his seminal paper on "Experimental Studies of the Perception of Movement." and was offered a lectureship.
From 1916 to 1925 he was in Berlin (as assistant professor form 1922 onwards). In 1925 he came back to Frankfurt as professor.
In 1933 he escaped Germany to the United States, where he taught at the New School for Social Research in New York City. There he wrote his book Productive Thinking.
Wertheimer is seen as one of the founding fathers of modern psychology.