The primary aim of this study was to detail anaesthetic techniques and complications for cataract surgery in the UK. The Cataract National Dataset was extracted from 12 National Health Service Trusts that used the same electronic patient record system between November 2001 and July 2006 on a total of 55,567 cataract operations. Anaesthesia was administered by an ophthalmologist in 56.7% of the cases, a career anaesthetist in 42.1% of the cases, a clinical assistant anaesthetist in 0.3% of the cases, and staff were not recorded in 0.9% of the cases. Local anaesthesia (LA) was used in 95.5%, with topical anaesthesia alone in 22.3% (range by site, 0-99.8%), topical and intracameral in 4.7% (range, 0-24.1%), subtenons in 46.9% (range, 0-81.8%), peribulbar in 19.5% (range, 0-63.4%), and retrobulbar in 0.5% (range, 0-5.3%). One or more minor complications occurred in 4.3% of 38,058 local blocks administered by either sharp needle or subtenons (blunt) cannula. Minor complications were 2.3 times more common with subtenons blocks (P<0.001). Serious complications, defined as sight or life threatening occurred in 25 eyes, 0.066%, undergoing sharp needle or subtenons cannula blocks. Sharp needle techniques had a 2.5-fold increased risk of serious complications compared with subtenons cannula techniques (P=0.026). Subtenons anaesthesia was the most widely used anaesthetic technique for cataract surgery but wide variation existed by site. There was a low rate of reported LA complications. There was a statistically significant increased risk of serious complications with sharp needle anaesthesia compared with subtenons technique.