A comparative study of intrathecal plain bupivacaine versus bupivacaine added with midazolam for subarachnoid block in lower limb surgeries and lower abdominal surgeries .  Methodology Patients were randomized as 30 patients each into two groups. Group ‘B’ - received 3.5 ml of 0.5% hyperbaric bupivacaine + 0.4 ml of 0.9% saline intrathecally. Group ‘BM’ - received 3.5 ml of 0.5%hyperbaric bupivacaine + 0.4 ml preservative free midazolam(5mg/ml) intrathecally.  Results The sensory blockade onset in group- BM was 165.76 sec and in group-B was 189.30 sec. The results were statistically highly significant (P-value<0.05).  Conclusion Based on the above study, the combination of 2mg preservative free midazolam and 0.5% hyperbaric bupivacaine for subarachnoid block in lower limb surgeries and lower abdominal surgeries prolonged the duration of effective analgesia as compared to plain bupivacaine and delays requirement of post operative analgesia . Intrathecal midazolam at a dose of 2 mg have no clinically significant effects on perioperative haemodynamics