In many countries, the growth of private label brands (PLBs) is negatively affecting manufacturer brands' shares, though PLBs have yet to take hold in other markets. Numerous studies have identified factors leading to the success of PLBs in product categories, and yet little empirical research has investigated the factors underlying the variability of PLB shares across countries. This research examines country-level market structure factors-retail distribution structure, retailer typology, and logistic structure- to understand the differential success of PLBs across countries. The results indicate that these factors help explain the dispersion pattern of PLB penetration across 46 countries and that the distribution structure has the largest effect on PLB share, followed by the logistic structure and retailer typology in particular global discounters. The findings can enable manufacturer brand managers to better foresee whether specific countries represent fertile ground for internationalizing their brands or, contrarily, constitute bastions for brand manufacturers to protect their brands' shares. The results also provide insights about the time frame over which PLB share development may pose a threat in different markets.