IDG Answers is a community of experts who are passionate about technology. Ask a question or answer one below.
40s probably isn’t going to be that big of a deal, and companies will never say they discriminate based on age, but obviously they still do, and the older the applicant, the more likely it is to occur. Honestly, I suspect many times it isn’t even a conscious decision. Think about it, you have some competent person in their late 20s in an interview for the same position as an equally competent 50 year old, who are you going to instinctively think is more “up to date”? Doesn’t mean it’s true, but I’d bet you that the majority of times, the 20-something is going to be preferred by the interviewer. Which echos Christopher’s point, I suppose. Plus (and this pains me to admit since I am no longer in my 20s), research shows consistently that more attractive people are more likely to get hired, and it was a heck of a lot easier for me to look good in my 20s than in my late 30s.
Age discrimination permeates all industries. IT is no different, sadly, so there's absolutely a chance it could be a "significant limiting factor" in your career.
What makes IT even harder on older workers is the formidable challenge of keeping up with rapid technological change. And even if an older IT worker does stay current, there's still the danger of him or her being perceived as out of touch.
It also should be noted that what often appears to be age discrimination actually is salary discrimination. Many companies won't hesitate to fire older workers with high salaries and replace them with cheaper young employees.