Disclosed herein is an information processing device including an acquiring unit that acquires positional information of a flat surface present in a first space around a first user and positional information of a flat surface present in a second space around a second user, and a transformation parameter determining unit that determines a coordinate transformation parameter for transforming position coordinates of the first space and the second space into position coordinates in a virtual space such that a position of the flat surface present in the first space and a position of the flat surface present in the second space coincide with each other. A position of an object present in the first space and a position of another object present in the second space are transformed into positions in the virtual space according to the determined coordinate transformation parameter.