"The history of the IT security industry is one of necessitated evolution: A new threat arises, IT responds. Driven by mobile, cloud, and remote-work megashifts, the new IT security model breaks this reactive cycle. The new IT security is adaptive, agile, cloud-based, and built on Zero Trust principles: Limit the opportunity for attack and minimize the potential for damage...because you can't steal what you can't see. Richard Stiennon has chronicled this revolution in Security Yearbook. It is vital reading for enterprise IT leaders looking to establish the best-in-world IT security capabilities of the future."
-Jay Chaudhry, CEO and founder of Zscaler

"Our future depends on the strength of our cyber infrastructure. Stiennon's experience and contribution to this industry makes him the best person to tell its story and his voice is the best one to help guide us into the future."
-Gil Shwed, Executive Chairman of the Board of Directors and founder of Check Point Software

"Cybersecurity is not just an industry, but a community of dedicated guardians of the digital world. Our common purpose and shared mission have created a vibrant culture, storied history, and boundless future, marked by noteworthy events and distinguished by remarkable individuals, fascinating companies, and captivating stories. Through his yearbook series, Richard Stiennon masterfully weaves together valuable industry research and sentimental reflection to encapsulate all that defines us, in a style that only he can deliver."
-Kevin Magee, Global Director of Cybersecurity for Microsoft for Startups

Security Yearbook 2025 is the sixth edition in an annual series. It is the story of the people, companies, and events that comprise the history of the IT security industry. In this edition you will discover the early history of Symantec, Network Associates, Borderware, Check Point Software, Netwitness, Tenable, Sourcefire, Quick Heal, Trend Micro and dozens of other companies that contributed to the growth of an industry that is comprised of 4,000+ vendors of security products. The Directory has been updated to reflect the change in headcount at each vendor during 2024.