Care.com

Care.com founder Sheila Lirio Marcelo got the idea for an online marketplace for care providers after she struggled to find qualified professionals to take care of her aging parents. Today, consumers can search on Care.com for child, senior, pet, and home care services, while providers can create profiles and search for jobs. The company pledges to keep customers safe by giving them the option of requesting a background check on any care provider they wish to hire. Though its services are popular--Care.com currently has more than 10 million members--it has struggled to become profitable. But the company believes that its growing international business, particularly its Berlin-based subsidiary, Care.com Europe GmbH, will help it keep its competitive edge. Note: employee count as of Dec. 31, 2015