This paper explores the factors that are most likely to drive high-growth firms (HGFs) in times of crisis. In an attempt to open the black box of this special type of firms, we examine the role of strategic modes of growth and knowledge processing capabilities of firms. We consider different forms of firm growth based on five alternative growth metrics, i.e. relative employment growth, absolute employment growth, birch employment growth, relative sales growth and absolute sales growth. For the analysis of HGFs, a particularly rich dataset is utilized based on a two-wave survey of 1,500 Greek firms conducted in 2011 and 2013. Our findings indicate that adopting an internationalization strategy significantly increases the likelihood of becoming high-growth in adverse economic conditions irrespective of the growth metric used. Specialized knowledge of employees, in-house R&D and diversification strategies are also found to play a relevant role in some cases.