Abstract: An apparatus for illuminating an archer's arrow that provides a nock adapted to receive a bowstring in a drawn position wherein a light source disposed withing the nock is activated when the bowstring is released from the drawn position. The nock provides a slot which is adapted to receive the bowstring. The slot provides a first widening portion adapted to receive the bowstring in a drawn position, and a second widening portion adapted to receive the bowstring when the bowstring is released from the drawn position. The nock also provides a bore which intersects at least a portion of the second widening portion of the slot. The light source is preferably a chemi-luminescent light stick which fits snugly within the bore of the nock. The bowstring engages and activates the light stick when the bowstring is released from the drawn position.