This work examines the possibility of changing the properties of the contact zone between fibres to control the physical properties of paper. This was done by linking the degree of contact of the contact zones in the fibre/fibre joints to joint strength, and furthermore, to the fibre and sheet properties. Kraft pulps of various yields were dried in order to collapse the fibre surface and fibre wall, to achieve a fibre with lower wet-fibre flexibility and fibre-surface deformability. This treatment produced fibres with lower water retention capacity and paper with lower sheet density, higher bending stiffness, and lower tensile strength. The changes in the sheet properties with drying were largely due to the decreased wet-fibre flexibility and deteriorated fibre contact-zone properties that reduced the fibre/fibre joint strength. By adding polyelectrolyte multilayers (PEM) or polyelectrolyte complexes (PEC), obtained from weak polyelectrolytes, to the dried pulp prior to fibre/fibre joint and sheet forming, the tensile and compression strength properties of the paper were significantly improved. Tensile strength increased up to 108% with no significant influence on either the sheet density or the water retention capacity of the fibres. Paper strength most likely increased due to the increase of the fibre/fibre joint strength arising from the improved contact-zone properties, where the increased work of adhesion and greater degree of contact of the fibre/fibre joints resulted in higher joint strength.