Hans Christian Jacobaeus performed the first clinical laparoscopic surgery in Stockholm. This pioneering procedure was based on the animal experiments of Georg Kelling (1866-1945), a German physician from Dresden, who performed the first laparoscopic intervention in 1901 using a Nitz cystoscope in a dog. In 1910, Jacobaeus published his initial experiences with laparoscopic surgery in the Münchner Medizinischen Wochenschrift under the title "The Possibilities for Performing Cystoscopy in Examinations of Serous Cavities." He used this technique for diagnostic purposes in undefined abdominal complaints and functional impairment. Jacobaeus was the first who pointed out the possibility of injuring organs, especially the intestines, by inserting the trocar. In 1910, Jacobaeus recognized the immense diagnostic and therapeutic possibilities of laparoscopic surgery, as well as its difficulties and limits. He also was the first to realize the need for initial endoscopic training in animals and corpses. He promoted the development of special laparoscopic instruments to optimize and simplify the procedure.