A computer system for enabling collaborative document markup between participants is provided. The computer system receives indicating data from a sensing device operated by a participant involved in a collaborative document markup session in conjunction with at least one document markup form containing information relating to the document markup session and including coded data indicative of an identity of the document markup form and of a plurality of map references of the document markup form. The indicating data includes data regarding the identity of the document markup form and a position of the sensing device relative to the document markup form. The sensing device generates the indicating data using at least some of the coded data when placed in an operative position relative to the document markup form. The computer system includes: means for identifying, from the indicating data, at least one parameter relating to the document markup session; and means for 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.