Prior to the 1990s, Argentine Tango was taught with a didactic method; teaching tango by having students copy examples shown by the instructor. Emphasis was not given to how or why movement was done a certain way. Starting in the 1990s in Buenos Aires, the Tango Investigation Group (later transformed into the Cosmotango organization) founded by Gustavo Naveira and Fabian Salas applied the principles of dance kinesiology from modern dance to analyze the physics of movement in Argentine tango. Taking what they learned from this analysis they then began to explore all the possibilities of movement within the framework of Argentine Tango. From the work of these founders of the Tango Nuevo movement, there was a shift in all styles of tango away from teaching what to dance toward teaching how to dance.