The last three decades has seen the construction of three separate and distinct types of manned undersea vehicles. These three categories are 1) military submarines, 2) manned submersibles and 3) tourist submersibles.
Over 50 examples of each category have been constructed since 1960.
Today, there are 11 countries that produce military submarines. Of these, only the United States, with 121 vessels, has a submarine force that is entirely nuclear powered. The former Soviet Union recently had a fleet of 311 submarines, 175 of which were nuclear. Great Britain, China and France have a mixture of both nuclear and diesel electric submarines, while the remaining submarine producers, Germany, Sweden, Japan, Italy, Netherlands, and Yugoslavia have relatively small fleets of diesel electric boats. The total number of submarines belonging to all 11 countries is approximately 649.
There are 32 additional countries that operate approximately 185 diesel electric submarines built by one or more of the 11 submarine producing nations. Approximately 50 midget submarines are estimated to be operational as well.
In the period from 1950 to 1980, well over 140 non-military manned submersibles were built world wide.
The list of tourist submersibles now has 56 entries that account for 1894 seats
