INTRODUCTION:Without mastery of the anatomy, luck rather than skill becomes the primary determinant of successful neural blockade. In this educational study our intent was to compare the level of nerve roots blocked by these two techniques of peripheral nerve block, widely used in clinical anesthesia practice. AIMS: To have a three dimensional view of nerve plexus involvement in inter scalene and supraclavicular techniques of brachial plexus block and compare in between them. MATERIAL AND METHOD: 6 recently deceased cadavers preserved in formalin were used. In both the techniques the classical methods usually pursued in daily clinical practice were followed. Dyes used were methylene blue and tartrazine of same dilution. RESULTS: Careful dissection showed that in all cases of inter scalene approach the dye was more concentrated in upper and middle trunk than in lower trunk of brachial plexus. In contrast in supraclavicular approach dye concentration was more in lower and middle trunk and less in upper trunk. DISCUSSION: After reviewing the anatomy it can be concluded that injection of local anesthetic at the interscalene level tends to produce a block that is most intense at the C5-C7 distribution and injection at supraclavicular level provide more compact anesthesia in C8-T1 distribution. CONCLUSION: Supraclavicular block is preferable for operations on the elbow, forearm, and hand and inter scalene block for shoulder.