Plato’s “Apology of Socrates” is a masterpiece of the philosophical literature. The question remains as to how much it has been influenced by earlier works, e.g. of Gorgias of Leontinoi and Euripides. Nevertheless, comparative studies on Hippolytus’ defense in Euripides’ tragedy of the same name, on Gorgias’ “Defense of Palamedes” and on Plato’s “Apology” do not exist. The short paper gives an introduction into the status quaestionis.