The key property for the load carrying capacity of paper materials is the interfibre joint strength. Due to the difficulty of testing the strength of such microscopic entities, the typical approach is to test isolated fibre-fibre crosses. In such experiments the joint is but one component of the tested structure and the flexural compliance of the long fibre segments results in a mixed mode of loading. Furthermore, the details of the failure mechanisms of such joints are as of yet unknown. A continuum description of the paper sheet is often insufficient to explain governing mechanisms when properties of the underlying structure are changed by mechanical or chemical modifications. Therefore network models are often used to take into account the underlying mechanisms. However, network models in turn rely on the properties of the fibres and of the interfibre joints. This paper aims to characterize the damage behaviour of isolated fibre-fibre crosses from three approaches: identifying typical damage features from an extensive number of mechanical tests of isolated fibre-fibre crosses; study the applicability of using cohesive zones to model the failure behaviour of inter-fibre joints; and, to study the influence of fibre and joint properties to the load carrying capacity of fibre-fibre crosses. The results indicate that the strength in the normal direction is significantly lower than in the shear direction and means on how to tailor the properties of fibres and joints for increasing the load carrying capacity is suggested.