This is the biggest organisation that specialises in recreational diversŐ training. It issues over 900 000 certificates per year and brings together about 100 000 professional trainers and diving guides. Within PADI there are also over 4 300 bases and diving schools placed in 175 countries. PADI training materials are available in 20 languages. Recently, a Polish edition of the book for the basic diving rank Open Water Diver has been published. In Poland PADI operates for not long time (since 1997). The organisation has been established in 1967 in the USA by John Crowin and Ralph Ericson who are the deputy and the chairman of this organisation respectively. Training according to PADI system is the same throughout the world.