The quantitative analysis of mass flow balance around the paper machine forming section, together with an appreciation of sheet structure, can be an effective tool in solving sheet quality problems. An earlier paper reviewed the fourdrinier sheet-forming process and made brief reference to the study of sheet structure by use of a transverse sheet-splitting technique. This paper, intended as companion reading to the earlier paper, describes further the techniques used to evaluate formation as a dynamic process and the application of those techniques to identify specific sheet characteristics. A case history pertaining to poor formation and curl is described. -- AATA