I applied for a green card through a sponsor a few years ago. I submitted the EAD application with the initial paperwork and had it within a month. I completed the Visa screen later that year, so no - you don't have to wait for it to apply for EAD. You do have to have the EAD to apply for work, though. A little tip - when you get it and it's time for renewal send the application about 3 months prior to the exp. date. When I did it the last time I had to leave the hospital I was working at because it did not arrive on time. Actually they changed the fee from $100 to $120 and did not process the aplication at all. I hope that helps. Maria