One could only witness the growing glider activity throughout the world since the pioneer deployments in the late 1990s. Worth mentioning are an impressive glider fleet demonstration which was carried out in 2003 in the framework of the experiment Autonomous Ocean Sampling Network (AOSN) II and several endurance lines that started to be maintained on both the West and East coasts of the USA. This activity has been growing in the USA since then, and in particular recently, in the framework of the Integrated Ocean Observing System (IOOS). In 2004, in parallel to the development of the glider activity in the USA, the first European glider experiments were carried out in the framework of the European project MFSTEP of the Fifth Framework Programme (FP5). Later, the European FP6 project MERSEA in 2006-2009, and later, several FP7 projects, as well as, several national past and on-going projects, (have) support(ed) glider operations in European and foreign waters. In the mean time, Australia has developed the ANFOG infrastructure to operate gliders in a sustained way.