After attending this Masterclass the attendees will have a sound understanding of the basics of thoracic paravertebral block (TPVB) and Thoracic interfascial plane blocks (PECS and serratus plane block). Sonoanatomy relevant for TPVB and interfascial plane blocks will be demonstrated in volunteers and the mechanism of action, pros, cons and limitation of each technique will be discussed. Participants will also be introduced to the concept of "sub - pectoral plexus block". Pre - recorded videos will be used to demonstrate how to perform these techniques. Hopefully this will build the foundation based on which the attendee can judiciously use these techniques for anesthesia and or analgesia in patients undergoing major breast cancer surgery.