Giovanni in the Anime is distinctly different from Giovanni in the Pokemon Games. Note that his appearance and role are slightly different, and also his presentation. Giovanni is first presented in the anime as a figure encased in shadow. Those who had not played the game did not recognize him as Giovanni the Gym Leader but "The Boss". He is seen always with his prized Persian at his side, like a rich powerful man. It is not revealed until much later that he is same character. We (the audience) wonder why Jesse, James, and Meowth take orders from this mysterious figure, as he is their boss and employer. Apparently, he gracious enough to grant them with funds that they continue to waste on useless things.
The distinct difference between these two versions of Giovanni is that the Giovanni of the game is incredibly and forcefully active while the Giovanni of the anime sits back while his lackies do all of his work. As seen as I compare the scene in the game where he is defeated in Silph Company and in the anime where Jesse, James, and Meowth [attempt to] do his dirty work. Meowth will have visions of Giovanni praising him as his prized pet but that is never the case. In the anime Giovanni is obsessed with finding only rare and powerful Pokemon, in this business it seems is where he gets his money (and also the Pokemon theme park seen in episode 17). Very little does he go out and do the work himself as seen in the game or in the manga.
His biggest achievement in the anime, however, was something that was only touched on in the game: Mewtwo. In the game, you are able to read the notes in Silph Co. about their experiments but it was never really explained if Giovanni really was behind it. In the anime, through his lust for rare Pokemon and power, he paid for the scientists to make a clone stronger than the original Mew. This was possibly his greatest achievement, to have this Pokemon that could defeat all others. His prize he lost twice. Unlike the Giovanni of the game, he does not entirely disappear, yet he becomes a comic relief.