Cataract surgery involves removal of a patient's clouded natural crystalline lens and implantation of a permanent artificial intraocular lens (IOL). It is generally a brief, painless procedure performed on an outpatient basis and most patients are back to their normal activities the next day after surgery. If both eyes have cataracts, usually they are removed one at a time, with a few days to weeks between each surgery to allow the first eye to heal and be evaluated in a follow-up exam for any possible problems.

Prior to surgery, the patient's eye is thoroughly examined to determine the proper power of the intraocular lens to be implanted and patients will discuss with their surgeon the various IOL options available. Some may choose regular monofocal lenses, while others opt for "premium" multifocal, or accommodating lenses, which can potentially restore a patient's ability to see without glasses at all distances post-surgery.

In the procedure itself, the eye is first dilated with eye drops and patients may be given a sedative to help them relax during the surgery. Local or topical anesthetic is applied to the eye to make the surgery painless. The skin around the eye is thoroughly cleansed, and sterile draping is placed around the patient's eye and head. Using an operating microscope, the surgeon makes at least one small incision into the eye at the edge of the cornea, through which the cloudy lens (the cataract) is then removed.

Usually the procedure is performed using an ultrasound-driven instrument that "sonically" breaks up the cataract (phacoemulsification), which is then suctioned (aspirated) out of the eye. This method is used most widely in modern cataract surgery today.

Special instruments may be used in another surgical method to mechanically break up the cloudy lens into small pieces (phacofracture), which are then removed directly from the eye through a small incision.
After the cataract has been removed, the surgeon will insert a new clear permanent artificial intraocular lens implant through the same tiny incision at the edge of the cornea. The lens Implant is inserted folded up initially and then allowed to unfold so it can be set in the correct position.

The tiny incision made at the edge of the cornea is usually self-healing, though in cases where micro-sutures may be used to close the incision they rarely need to be removed.

Recovery from cataract surgery is very brief, with patients often spending no more than 90 minutes from prep to release and most people return to their normal activities within a day after surgery.