Scuba/SDI

Scuba Diving International (SDI)
SDI/TDI

Scuba Diving International (SDI) and sister company Technical Diving International (TDI).

http://diveaddicts.com/images/261.jpg

"Scuba Diving International (SDI) is a Scuba training and certification agency. It is the recreational arm of Technical Diving International, the world’s largest technical diver training organization." 

Scuba Diving International - Wikipedia - http://en.wikipedia.org/wiki/Scuba_Diving_International

"“Scuba Diving International” was created in 1999 and grew out of the success of its sister company TDI, which specializes in the more advanced disciplines of technical diving. SDI is the only scuba training and certification agency to require students to be taught with modern dive computers from the onset of training. SDI is also unusual amongst recreational diver training organizations in that it recognizes solo diving as part of recreational diving, and offers a special training course relating to it.(www.tdisdi.com)"

"“Technical Diving International” is the largest technical certification agency in the world. As one of the first agencies to provide training in mixed gas diving and rebreathers, TDI is seen as an innovator of new diving techniques and programs that were previously not available to the general public.(www.tdisdi.com)"

Certification
Learn to Scuba Dive - http://www.tdisdi.com/sdi/get-certified/