The first edition of the summer webinar series titled Advances in Subsurface Mechanics for Energy and Environment was conducted at IIT Madras in the months of July–September 2021. The series hosted leading researchers from academia and industry to discuss pioneering research in the broad area of subsurface mechanics. The choice of topics was diverse and included experimental and computational geomechanics, multiphase flow and reactive transport modeling, subsurface characterisation, geochemistry, and their applications in oil & gas and geothermal energy industries.