Abstract: An adjustable hinge is disclosed, which comprises: a) two hinge bodies for attachment, respectively, to a window or door frame and a window or door leaf; b) a rotating pin suitable for mutually articulating the hinge bodies; and c) a member for adjusting shared positions of the hinge bodies in a direction generally perpendicular to the axis of the pin. The adjustment member includes a sleeve, associated axially with the pin, which defines an external lateral coupling surface with a corresponding housing defined in a first of the hinge bodies. The sleeve is pivotally engaged with the housing such that, while remaining in relatively continuous contact with the walls of the cavity during rotation to change its position, it may occupy substantially any position required along a limited length in the perpendicular adjustment direction.