M1 - Confronting Sarif is a mission in Deus Ex: Human Revolution.
Meet Sarif in your apartmentEdit
Now that you're back from your overseas adventures, it's time to get back to work in Detroit. First up, talking to Sarif. The conversation with Eliza raised a lot of questions and Sarif needs to answer them.
In the back corner of the helipad area there's a hidden room which can be accessed via a weakened wall. Use the Punch Through Wall augmentation (or use explosives/shoot at it) to break through. Inside you'll find an ammo capacity upgrade (on top of the lockers) and an energy bar (inside the lockers). Use the crate (or jump-crouch) to go into the vent to find a credit chip.
There's a credit chip by the patio tables as well.
Continue into the building and take the elevator down to meet with Sarif. He will give you instructions on your first real mission back in the city: Finding Isaias Sandoval.