The project of extension at sea of Monaco required the realization of important environmental measures to protect the marine environment. Among differents actions was included a significant experimental measure of transplantation of nearly 500 m2 of Posidonia oceanica located in the project area. To reach this objective we have developed and implemented the SafeBent protocol. The SafeBent protocol allows to sample clods of seagrasses (0.8 m2/60 cm thick) with a marinized transplanter (Model Optimal 880) operated with a very long arm shovel (27 m) from a jackup. The main advantages of this method are:-high transplantation rate (up to 32 m2/jour);-conservation of the structure of the seagrasses in meadows;- conservation of the sediment;-easy transport of clods in specially manufactured metal baskets The transplantation was carried out between 20 March and 15 May 2017. Seagrasses were reimplanted in the ground of the AMP of Larvotto (384 m2) and on the berm of the dam along the port of Fontvieille in specially constructed concrete planters (116 m2). The present communication aims to present the Safebent method and the results obtained to date.