The advent of micro-invasive glaucoma surgery (MIGS) has redefined the role of gonioscopy, elevating it to a critical skill set necessary for contemporary glaucoma management. Proficient gonioscopic evaluation—encompassing the detailed observation and identification of anterior chamber angle structures—and the ability to perform precise angular procedures expand the surgical options available for treating glaucoma. This approach offers the significant advantage of extended bleb-free and tube-free years, enhancing patient’s quality of life. This chapter explores the refined techniques required to accurately perform trabecular meshwork/canal-based MIGS and reviews the various types of MIGS, highlighting their indications, surgical technique, and clinical results. By fostering a deeper understanding of these skills, the authors aim to equip clinicians with the tools to navigate the evolving landscape of glaucoma care, ensuring the best possible outcomes for their patients.