This volume is the proceedings of the workshop on ‘Algebraic Varieties and Automorphism Groups’ which was held at RIMS, Kyoto University during July 7-11, 2014.The volume consists of fifteen original research articles by specialists in fast developing areas of algebraic geometry including various aspects of algebraic varieties (singularities, toric surfaces, weak positivity of log canonical pairs, Fano threefolds with cylinders, etc.), algebraic group actions on algebraic varieties (actions of additive group, unipotent group, semi-abelian variety, etc.), automorphism groups of affine varieties and Cremona groups.Highly recommended to researchers and graduate students interested in research trends in affine and projective algebraic geometry and algebraic group actions.Published by Mathematical Society of Japan and distributed by World Scientific Publishing Co. for all markets except North America