A comparative double-blind study has been made of 0.5 O/o bupivacaine (Marcainea) with adrenalin 1 :200 000, 0.5 O/o bupivacaine plain, and 2 O/o mepivacaine (CarbocaineB) with adrenalin 1 :200 000, in a series of 35 patients undergoing cataract and glaucoma surgery. The onset time of analgesia did not differ in the groups, but the onset of akinesia in orbicularis, and especially in the extraocular muscles, seemed longer in both bupivacaine groups. The duration of analgesia was about one and a half times as long, and that of akinesia about twice as long in the two bupivacaine groups as in the mepivacaine/adrenalin group. In the bupivacaine plain group an increased tendency towards conjunctival bleeding was observable during the operation; consequently, bupivacaine with adrenalin is preferable.In ocular surgery, 0.5 O/o bupivacaine with adrenalin offers a good choice of local analgesic agent when local anesthesia must last a long time. Due to its slow onset, the local blocks have to be administered at least 30 minutes before the surgery is begun.In intraocular operations, temporary paralysis of the orbicularis oculi and the extraocular muscles, together with blocking of the postganglionic fibres of the