A system for accessing a surgical target site, comprising: a dilation system advanceable to create a lateral trans-psoas path to a targeted spinal site including at least a portion of a spinal disc, wherein said dilation system includes a K-wire having a distal end portion that is penetrable into an annulus of the spinal disc, a plurality of dilators (44, 52, 54) advanceable to the targeted spinal site along the lateral trans-psoas path, at least one dilator of the plurality of dilators being advanceable over another dilator of the plurality of dilators to the targeted spinal site along the lateral trans-psoas path; at least one of the K-wire and a dilator of the plurality of dilators having a stimulation electrode that is configured to deliver electrical stimulation for nerve monitoring when the at least one of the K-wire and a dilator of the plurality of dilators is positioned along the lateral, trans-psoas path; a three-bladed retractor assembly having first, second, and third blades (12, 16, 18) which are releasably coupled to first, second, and third moveable arms (17, 26, 28) of a handle assembly, the first, second, and third blades capable of being advanced simultaneously to the surgical target site while in a closed position and thereafter selectively opened to create an operative corridor to the surgical target site, the first, second, and third blades (12, 16, 18) being slidable over at least one dilator of the plurality of dilators along the lateral, trans-psoas path to form the operative corridor along the lateral, trans-psoas path to the targeted intervertebral disc, wherein the second moveable arm is configured to pivotally move the second retractor blade relative to the third retractor blade and the third moveable arm is configured to pivotally move the third retractor blade relative to the second retractor blade, and wherein the first moveable arm is configured to linearly move the first retractor blade relative to the second and third retractor blades (16, 18), wherein the retractor assembly includes a rotatable actuator operable to linearly move the first arm independent from the pivotal movement of the second and third arms, the retractor assembly being adjustable from a first position in which the plurality of retractor blades are positioned to slide over at least one of the plurality of dilators to a second position in which the plurality of retractor blades are spaced apart from one another to enlarge the operative corridor; and wherein when the bladed retractor assembly forms the operative corridor along the lateral, trans-psoas path to the targeted intervertebral disc, the operative corridor is dimensioned so as to pass an implant through the operative corridor along the lateral, trans-psoas path toward the targeted intervertebral disc of the lumbar spine. a dilation system advanceable to create a lateral trans-psoas path to a targeted spinal site including at least a portion of a spinal disc, wherein said dilation system includes a K-wire having a distal end portion that is penetrable into an annulus of the spinal disc, a plurality of dilators (44, 52, 54) advanceable to the targeted spinal site along the lateral trans-psoas path, at least one dilator of the plurality of dilators being advanceable over another dilator of the plurality of dilators to the targeted spinal site along the lateral trans-psoas path; at least one of the K-wire and a dilator of the plurality of dilators having a stimulation electrode that is configured to deliver electrical stimulation for nerve monitoring when the at least one of the K-wire and a dilator of the plurality of dilators is positioned along the lateral, trans-psoas path; a three-bladed retractor assembly having first, second, and third blades (12, 16, 18) which are releasably coupled to first, second, and third moveable arms (17, 26, 28) of a handle assembly, the first, second, and third blades capable of being advanced simultaneously to the surgical target site while in a closed position and thereafter selectively opened to create an operative corridor to the surgical target site, the first, second, and third blades (12, 16, 18) being slidable over at least one dilator of the plurality of dilators along the lateral, trans-psoas path to form the operative corridor along the lateral, trans-psoas path to the targeted intervertebral disc, wherein the second moveable arm is configured to pivotally move the second retractor blade relative to the third retractor blade and the third moveable arm is configured to pivotally move the third retractor blade relative to the second retractor blade, and wherein the first moveable arm is configured to linearly move the first retractor blade relative to the second and third retractor blades (16, 18), wherein the retractor assembly includes a rotatable actuator operable to linearly move the first arm independent from the pivotal movement of the second and third arms, the retractor assembly being adjustable from a first position in which the plurality of retractor blades are positioned to slide over at least one of the plurality of dilators to a second position in which the plurality of retractor blades are spaced apart from one another to enlarge the operative corridor; and wherein when the bladed retractor assembly forms the operative corridor along the lateral, trans-psoas path to the targeted intervertebral disc, the operative corridor is dimensioned so as to pass an implant through the operative corridor along the lateral, trans-psoas path toward the targeted intervertebral disc of the lumbar spine.