The book aims to expand knowledge of this new cancer treatment technique in veterinary medicine. It is an extended literature review, which provides an approach so that the reader can understand the principle of this new therapeutic modality, its history, technique, indications and expected results. Nowadays, pets are considered to be members of the family, so owners are looking for more sophisticated treatments to prolong their pet's life. Electrochemotherapy is one of these alternatives, saving many lives, with the fewest possible side effects and the shortest treatment time.