Experimental results and theoretical predictions for failure of timber beams with end notches, or cuts on the tension face, are discussed. The validity of Gustafsson's formula and the underlying assumptions are examined in the context of structural design codes. Attention is drawn to the arbitrary dependence of theoretical predictions on the load and geometric arrangement of specimens, and the method by which fracture energy is estimated. It is not intended at this stage to give a complete solution for the problem, but it is concluded to be premature to incorporate the proposed Eurocode 5 failure criterion for notched beams into the Canadian Standard CAN/CSA 086.1. Key words: timber, fracture, notched beam, design criterion.