It comes out in June. And you go to work with your sims.
"The Sims 3 Ambitions allows players to control their sims while they are at work in a variety of new careers. Instead of sending your sims off to work all day, The Sims 3 Ambitions lets you pick a career like firefighting, investigator, architect, ghost hunter, stylist, or doctor and then guide your sim to make choices and succeed (or fail) every step of the way. You can also make your sim a tattoo artist, sculptor, or inventor. "