Yielding pillar theory and the comparative performance of yield-pillar-protected roadways to critical and stable pillar systems are described. The applicability of empirical methods, the mine stiffness concept, enhanced confined core concept and numerical modelling in designing a yield pillar during the development stage of mining in two-entry systems was investigated and the drawbacks of each method are outlined. These methods were compared by evaluating published data from field measurements. Finite difference models were arranged for estimation of strata stiffness at the pillar location for comparison with the post-failure slopes of pillars of 5, 7.5 and 10 m in width, which are the intended preliminary design for a UK coal mine. The estimated pillar width ranges of the methods for this example were compared. The findings are verified by those from previous investigations.