Abstract: Finding new buyers is crucial for firms to expand their business. This paper studies the role of labor mobility as a mechanism for acquiring buyers from rival firms. We focus on one type of worker likely to build ties with buyers: sales managers. Combining French firm-to-firm trade data with matched employer-employee data, we perform an event-study design that exploits the timing of sales managers’ recruitment for identification. We find that recruiting a sales manager increases significantly the probability to start selling to the buyers of her former firm. Having interacted with a buyer in the past multiplies the probability for the new recruit to sell to this buyer in the future by 11 times. Such business network transmission comes at the expense of the buyer’s former suppliers and, in particular, the sales managers’ former employer. Yet, business stealing is only partial, which leads to job-to-job transitions not being zero-sum. The investigation of mechanisms reveals that sales managers accumulate buyer-specific connections, beyond country- and sector-specific knowledge.