Mash bean [Vigna mungo (L.) Hepper], is the third largest pulse crop in Pakistan. Nine advanced breeding lines were compared with two commercial varieties, in order to investigate their potential prior to release as cultivated varieties. A field experiment was conducted in three environments in Punjab, Pakistan, during the 2014 kharif (wet) season. Developmental, morphological and yield traits included time to reach 90% maturity, plant height, the number of branches, grain yield (GY) and its components. GY varied between 778 kg ha -1 (cv. Mash Arooj) and 1005 kg ha -1 (line 11CM-709) in the eleven genotypes, and between 438 and 1667 kg ha -1 in the three environments. The lowland environment (Piplan) was the highest yielding, despite significant water deficit. In each genotype average yield across the three environments, plotted against the regression slope of specific yield vs. average yield in each environment, allowed yield potential and stability to be shown. As a result, five breeding lines exhibited a remarkable yield potential in exchange for low stability, i.e. modest suitability for low yielding environments. The remaining lines yielded as the two commercial varieties with a higher stability across environments. These are good premises for mash bean wider diffusion in the surveyed area.