Qualys, Inc. provides cloud security, compliance and related services and is based in Foster City, California. Qualys provides vulnerability management solutions using a "software as a service" (SaaS) model. It has added cloud-based compliance and web application security offerings.

Qualys has over 10,300 customers in more than 130 countries, including a majority of the Forbes Global 100. The company has strategic partnerships with major managed services providers and consulting organizations including BTDell SecureWorksFujitsuIBMNTTSymantecVerizon, and Wipro. The company is also a founding member of the Cloud Security Alliance (CSA).