We study the relationship between industry variety in a start-up's home location and the start-up's internationalization in terms of both the likelihood of and persistence in exporting. Using a unique sample of Swedish start-ups, we find that related industry variety is positively associated with exporting likelihood and persistence, whereas unrelated industry variety is positively associated with exporting likelihood and persistence when the start-ups’ employees possess technological knowledge. We also find that employees’ international experience strengthens the positive relationship between related industry variety and start-ups’ export persistence. We provide auxiliary evidence of the proposed mechanisms through which related and unrelated industry variety affects start-ups’ internationalization—that is, through their effects on start-ups’ ability to launch novel products in foreign markets. The findings of our study provide policymakers preliminary evidence on the value of developing and sustaining local knowledge conditions and promoting labor recruitment policies in the home country to promote start-up internationalization.