American businessman Leonard Bosack is one of the founders of Cisco Systems, a multi-national corporation which specializes in designing and selling communications technology, networking services, and consumer electronics. He co-founded the company with Sandra Lerner, who later became his wife.

For founding Cisco Systems, Bosack was selected as a recipient of Computer Entrepreneur Award. He was influential in the commercialization of LAN (local area network) technology in connecting computers that are geographically disparate through a multiprotocol router system which was yet unknown during that time.

In 1990, Bosack resigned from the company, while his wife was fired by the management. Currently, Bosack serves as the chief executive officer of XKL LLC, a private engineering company that develops and explores optical networks that are used for data communications.