Shrihari Sridhar served as Area Editor for this article.
For retailers, format portfolio management is a core marketing operation, but has received little attention in the marketing literature. This study analyzes the relationship between format diversification and retailer performance in a global setting, where retailers as part of their geographic expansion process often employ format diversification. The dual strategies of geographic diversification and format diversification substantially complicate the diversification-performance relationship. Using a six year panel data set for leading global retailers, we find a positive impact for geographic diversification, a negative impact for format diversification and a negative interaction for the dual strategies, supporting a single focus diversification strategy. We further show the consistency of our findings using a series of model robustness checks.