Chemodenervation by botulinum neurotoxin (BoNT) has significantly evolved over years since Alan Scott first described its use in 1970s for treatment of strabismus. It has been used for a wide variety of diseases. It has surpassed other treatment options to become the first line of therapy among oculoplasty surgeons for facial dystonias and as an aesthetic agent. The effect of BoNT is temporary but as a well-maintained therapeutic effect even after repeated injections. The side effects and complications are very rare, and it is often temporary. In this article, we review the pharmacology, indications in ophthalmic plastic surgery, techniques, and adverse effects of BoNT.