Case Study: Day & Zimmermann achieves CUI compliance and seamless offline MFA for its mobile workforce with Duo Security

Day & Zimmermann - Customer Case Study

Day & Zimmermann (D&Z) is a large private contractor specializing in construction, engineering, staffing and defense services, operating globally and handling Controlled Unclassified Information (CUI) under strict DFARS and NIST SP 800‑171 rules. With many employees working at remote client sites or traveling (roughly 1,500 regularly offline), D&Z needed two‑factor authentication at login/unlock to secure endpoints and remain contract‑compliant while keeping a consistent, low‑friction user experience.

D&Z deployed Duo in 2014—initially for Cisco VPN and now protecting Outlook Web Access, Citrix, Thycotic, Passwordstate, RDP and more—and relies on Duo’s offline MFA so users can authenticate without internet access. The rollout was smooth, more cost‑effective than the legacy token solution, maintained a transparent user experience across online/offline contexts, and helped D&Z meet regulatory requirements while reducing support burden.

Day & Zimmermann

Lance Honer

Manager of Cybersecurity