Although many regarded transwarp drive as an impossibility, recent experience has shown that transwarp is indeed possible. In 2364 the USS Enterprise made several short transwarp flights with the assistance of an alien being known as "The Traveller". In 2369 the Borg invaded Federation space for the third time, under the command of the android Lore. This time the Borg used a transwarp vessel capable of generating conduits within which an object could travel at incredible speeds - the USS Enterprise accessed one of these conduits and made a short trip at an average of some 236,000,000 times light speed. This vessel, which is thought to have been an advanced prototype, was later destroyed by the Enterprise. The crew of the USS Voyager, who had tested their own transwarp drive in 2372, encountered a transwarp-capable species known as the Voth while journeying in the Delta Quadrant. A typical Voth ship was capable of some 200,000 times light speed using their transwarp drives. Voyager has subsequently encountered the Borg, and has confirmed that a form of transwarp utilising conduits is in widespread use by this species. The Borg maintain six transwarp hubs, each of which maintains a network of many conduits spreading throughout the galaxy. Vessels entering this network can cross the galaxy in a matter of minutes at speeds in equivalent to more than a billion times that of light. In 2377 Voyager managed to destroy one of these hubs, disabling Borg activity across a huge section of the galaxy. Borg vessels also use transwarp coils to generate conduits.

When Professor Terrance and Doctor Neltorr proposed their "TNG scale", they had shown that a graph of the power required to propel any object at warp speeds would show certain minima which matched integer warp factors. On the TNG scale the velocity of an object - under ideal conditions - would be given by raising the warp factor it was travelling at to the power of 10/3, up to warp factor nine. Beyond warp nine the exponent increased gradually, then sharply as warp 10 was neared. At warp 10 itself the exponent became infinite - an object reaching warp 10 would thus achieve infinite speed, passing through every point in the universe simultaneously. Standard warp drives required infinite power to achieve warp 10 - naturally this seemed an impossible task. Scientists of the day where quite confident in proclaiming Warp 10 as the ultimate impassable barrier. In 2269, scientists working for the Daystrom Institute took the theoretical models of subspace created by Terrance and Neltorr one step further. It was realized that the mathematics allowed for a second subspace region stretching from the warp 10 barrier up to another, similar barrier at warp 20 - a region which a public relations officer in the Daystrom Institute press office dubbed the "transwarp domain", a name which has stuck despite its inaccuracy. In 2270 it was realized that even this theoretical transwarp domain was only part of the whole structure. The theory allowed for an infinite number of such domains, each separated by a warp barrier. Throughout the early 2270's there was a huge effort to discover whether these transwarp domains where just theoretical constructs, or where actually real. In 2273 the Starfleet science vessel USS Wanderer conducted a subspace particle dissipation experiment which proved conclusively that not only did transwarp domains actually exist, but that under certain circumstances it was possible for matter to circumvent the warp barrier and pass into the transwarp domain. Theoretical and practical studies quickly established that at a point infinitesimally past Warp 10, the warp factor exponent fell from infinity to zero and then began to gradually rise again. By Warp 11 the exponent reached 13/3, after which it mirrors the behaviour of the normal warp curve. A Warp 19 the exponent begins to climb, again reaching infinity at warp 20 to form the next warp barrier. The whole process is repeated again in the second transwarp domain, and again in the third, and so on. In each domain the 'steady' central value of the exponent increases linearly - from 10/3 in the warp domain to 13/3 in the first transwarp domain, 16/3 in the second, then 19/3, 22/3, and so on.

The speeds of warp factors within the warp domain and the first two transwarp domains can be seen on following chart:

Today a workable, practical transwarp drive remains beyond the reach of Federation science and although some efforts to develop this technology are still being made, no progress has yet been achieved.