1. A method of enabling collaborative document markup between participants, the method including the steps of: providing a participant with at least one document markup form containing information relating to a collaborative document markup session and including coded data indicative of an identity of the document markup form and of at least one reference point of the document markup form; receiving, in a computer system, indicating data from a sensing device operated by said participant involved in the document markup session, said indicating data regarding the identity of the document markup form and at least one of a position and a movement of the sensing device relative to the document markup form, the sensing device, when placed in an operative position relative to the document markup form, sensing at least some of the coded data and generating the indicating data using at least some of the sensed coded data; identifying in the computer system and from the indicating data, at least one parameter relating to the document markup session; and providing at least one other participant remote from said participant with at least one document markup form containing information representative of the at least one parameter, wherein the sensing device is further adapted to store a sensing device identifier which is adapted to distinguish the sensing device from other sensing devices of the same type.