Day is Symantec's acting chief technology officer and director of security strategy, responsible for seeing through the firm's plan of action across Europe.
As well as his role at Symantec, Day is also the current vice chair of technology trade association, Intellect's cyber security group.
Prior to his twin roles Day spent 12 years working for McAfee, leaving the firm after a stint as its director of security strategy.
Earlier in the year fellow security heavyweight Eugene Kaspersky also took to V3's Hot Seat.
If you want to volunteer for V3's Hot Seat, or want to suggest an IT leader you think should take part, please email: Rosalie.Marshall@incisivemedia.com for more details.
V3: What would be your dream job (apart from your current role, of course)?
Greg Day: I'd love to be a golf pro.
Which mobile phone and tablet do you currently use?
Apple times four - I have an iPhone 5 and an iPad, and that's in addition to my iPod Nano and my MacBook Air.
Which person do you most admire in the IT industry?
There have been lots of breakthroughs over the years and many clever people have done great things in IT, but I firmly believe that the best is yet to come.
Which technology has had the biggest impact on your working life?
Smart devices, for the simple reason that I am always connected. Although this can definitely be both a blessing and a curse.
What's been the highlight of your career so far?
I enjoy witnessing the moment people ‘get it' - that instant when someone fully understands or can make sense of all the opportunities, and challenges, that technology presents. This can occur from government, to companies and right down to individuals.
What was your first job?
A Saturday milk round, probably before legal working age! My first proper job was technical support at Dr Solomon's Antivirus.
What's your favourite thing about working in the IT industry?
The diversity. Absolutely every day is different. Show me an industry that is so fast moving - from new technologies to new risks.
What will be the next big innovation of the coming years?
The death of the credit card - it will be replaced by smart devices. This technology is still in its early stages but will be the payment method of choice within the next five years.
What was the last book you read and was it any good?
I read a lot of action thrillers. The last one was A Devil is Waiting by Jack Higgins - it was very good.
Do you prefer e-readers or real books?
Twitter, Facebook or Google+?
Twitter. It's my external communications manager and good for breaking news. I use LinkedIn for managing my network.
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