Tango Nuevo is a dancing and teaching style. Tango nuevo as a teaching style emphasizes a structural analysis of the dance in which previously unexplored combinations of steps and new figures can be found. It is a result of the work of the "Tango Investigation Group" (later transformed into the "Cosmotango" organization) pioneered by Gustavo Naveira and Fabian Salas in the 1990's in Buenos Aires. By taking tango down to the physics of the movements in a systematic way, they have created a method of analyzing the complete set of possibilities of tango movements, defined by two bodies and four legs moving in walks or circles. This investigation provided a view of a structure to the dance that was expressed in a systematic way.
In walks, their explorations pioneered what were once called "alterations" and are now called "changes of direction". In turns, they focus on being very aware of where the axis of the turn is (in the follower/in the leader/in between them). This tends to produce a flowing style, with the partners rotating around each other on a constantly shifting axis, or else incorporating novel changes of direction.
Many of the recent popular elements in tango vocabulary, such as single-axis turns, owe their debut on the tango scene to the popularity of Gustavo's and Fabian's approach.
From this teaching style, a new and unique style of dancing has developed, called by many a "tango nuevo" style. The most famous practitioners of "tango nuevo" are Gustavo Naveira, Fabian Salas, Chicho Frumboli, and Pablo Veron. Interestingly enough, all four of these dancers have highly individual styles that cannot be confused with each other's, yet can be easily recognized as "tango nuevo".
Tango Nuevo is often misunderstood and mislabeled as "Show Tango" because a large percentage of today's stage dancers have adopted "tango nuevo" elements in their choreographies.
(from Wikipedia (http://en.wikipedia.org/wiki/Tango_(dance)#Tango_Nuevo))