Fibre reinforced cements are of considerable industrial importance, the production of asbestos cement amounting to about 5 m tonne per annum. The search for fibres other than asbestos has led to the investigation of glass, polypropylene, cellulose (and other fibrous materials) in a cement matrix. Whilst there has been much work on the fibrous component of cement-fibre composites little attention has been paid to the effect on the final composite properties following improvements in the cement matrix. The preparation of macro-defect-free (MDF) cements has recently been reported and the work presented here describes the preparation and the properties of fibre-reinforced MDF cement composites. The Young's modulus of elasticity and the strength of MDF cements are greatly improved and do not need fibrous reinforcement to show benefit. The main purpose of reinforcing MDF cement with fibres is to enhance toughness and impact performance. It is shown that small volume fractions of fibre (∼2%) in the MDF cement matrix produce composites with excellent toughness and impact properties.