In cataract surgery, several types of intraocular lenses (IOLs) are used to replace the clouded natural lens. While several designs exist, including monofocal, extended depth of field, and multifocal lenses, the process for insertion generally remains the same except for toric lenses, which must be dialed into the correct orientation. The ideal location for implanting an intraocular lens is within the capsular bag, which offers optimal stability for the IOL and positions it closer to the nodal point of the original crystalline lens, leading to enhanced image resolution (Snead MP, Lea SH, Rubinstein MP, Reynolds K, Haworth SM. Determination of the nodal point position in the pseudophakic eye. Ophthalmic Physiol Opt 11(2):105–108. https://doi.org/10.1111/j.1475-1313.1991.tb00207.x , 1991). This placement also minimizes the risk of complications involving the endothelium and anterior chamber angle by keeping the foreign lens material away from the anterior chamber. However, when it is not feasible to securely position the IOL within the capsular bag due to factors such as posterior capsule rupture, zonular laxity, lens subluxation without a capsule, or planned piggyback IOL placement, an alternative positioning and fixation method is necessary. Usually, placing a three-piece IOL in the sulcus is the next best option if the anterior capsule and zonules are intact. Anterior chamber and scleral-sutured IOLs will not be discussed in this chapter (Hausheer JR, ed. Basic techniques of ophthalmic surgery, 3rd ed. American Academy of Ophthalmology, 2019).