Unequivocally, Iago plays an important and major function in the tragedy of Othello. By the end of the play, Iago has been directly responsible for the deaths of Roderigo, Emilia and the protagonist and his love. Iago's importance to the play is revealed by his contribution to the plot and his significance relative to other characters. Iago's function, which invariably adds to the importance he has on the play, is to lead to the downfall of Othello therefore revealing the themes of hate, jealousy and revenge. Iago also serves to contrast with the characters of Othello and Desdemona and to create dramatic irony consequently involving the audience in the journey of the play. The foundation of his success has been built upon his honest reputation, perceptive nature and ruthless motivation.

             Iago's importance to the play is revealed through the significance he has in determining the direction of the plot. Just like a masterful puppeteer, he has forcefully steered its' direction. Shakespeare, at the very beginning of the play does not bother to develop the character of the protagonist, Othello but rather places greater emphasis on plot development. We are immediately introduced to Roderigo and Iago and are privy to their conspiracy to undermine Othello. With a masterful stroke, Iago subdues Roderigo, his 'dupe' and sets up the initial plot- Iago intends to gain his rightful position of lieutenant by destroying Othello and Casio. "I Know my price, I am worth no worse a place." Although Iago's plan does not change throughout the play, his motives, which obviously influence his actions do. Iago's initial motive in destroying the protagonist is hatred. "I hate the Moor." This shifts to jealousy, "He's done my office", to just sheer malignant motives. "If Cassio do remain he hath a daily beauty in his life that makes me ugly." It is as if Iago has allowed us to follow his journey from revenge to finally madness.