This review provides a general view on teleost germline development using primordial germ cells (PGCs) or spermatogonia (SG), highlighting recent progress in research on these two cell types in teleost fishes. Due to the interest of these cells for gene banking purposes, this chapter also reviews the available protocols for cryopreservation and the techniques that have been employed to assess cellular and molecular status after the process. Protocols for in vitro culture and the possibility of generating PGCs in vitro from non-committed embryonic cells are also discussed. Furthermore, the potential of these cells in surrogate production is presented, analyzing the transplantation and xenotransplantation experiments performed in fish.