CBT, or something closely related to it, tends to resurface in a new form every five years or so. It becomes attractive when people realise the benefits that a well-designed implementation can bring, then it fades into the background after it becomes an industry fad - attracting the attention of people who are unaware of the do's and don'ts that help a CBT project be successful. Those projects fail, and people forget about CBT until the next time.

And that's a shame - because CBT can be an efficient, powerful, and above all else cost-effective way for organizations to meet their training needs.

If you have a lot of people to teach, or a group of people who are widely separated, or folks who don't work the same hours as the people who would otherwise be able to teach them, then why not use a computer to support their learning instead? The idea's not new - I've been working in the field for more than thirty years - but as computers become more powerful and the technology they support gets more sophisticated, and particularly as the Internet develops, it's getting easier and easier to do.

Using a computer to deliver training content has a number of advantages:

• It's available 24 hours a day, 7 days a week.
• It's consistent; the same material is presented each time.
• It's scalable; if you have a larger audience, they can all be trained without having to recruit more trainers
• Students don't have to travel to a trainins centre to receive training. Training can be delivered via the Internet or a secure VPN.
• It's responsive; it can trap common errors or misconceptions and mitigate student mistakes with additional content. That frees up teachers or instructors to deal with the more interesting, harder instructional challenges.

The big difference between working with a computer program and reading a book is that the computer program - if it's been designed properly - can pay attention to you. It can check that you're actually understanding what you're experiencing. This may be as simple as asking a question about the subject matter; if you get it right, you can continue. If you can't answer the question correctly, then the computer should present some additional training material to give you another opportunity to learn. People are all different, and to a certain extent we learn in different ways. If you don't "get it" one way, try another.

So, a computer can be programmed to act a little bit like a teacher, making sure your attention stays focused, and checking that you're keeping up with what's going on. All of which is difficult for a book to do.

It's difficult for TV, too - even the educational shows just happen at you. Even the red button of "digital interactive" shows doesn't have that much of an effect on the content. The programmes will be the same whether you watch them or not. The fundamental idea of technology-based training is that it should be interactive in the fullest sense of the word. In other words, what you do affects the training you receive. You make a difference.

Strangely enough, many training projects fail at the first hurdle - or if they don't fail outright, they make life very difficult for the project's duration - because this question isn't examined in enough detail.

The identification of the training requirements takes place by carrying out a Training Needs Analysis, or TNA. There are a number of methods for carrying out a robust and reliable TNA and I've used several of them. The outcome of your TNA should set out the goals of the training (what your students will be expected to do once they've completed their training) but it should also cover the Training Options: how the training should be delivered, and even what the cost would be of doing nothing.

The answer's a glib one, but only because it's true: it depends on the requirement. You might find that a simple web-based solution with a suite of pages of content will completely meet your needs. Or you might need a more complex solution involving blended learning, or any of a hundred other ways in which computers can deliver training.

You don't have to. But I have got a lot of experience in the field. I started working on CBT and distance learning projects in the 1980s at BT. BT's Distance Learning Unit were at the vanguard of serious technology-based learning, working in conjunction with external companies to develop powerful training applications on media as diverse as cassette tape and interactive videodisc. I got very involved in user support in that job, which led to a fascination with UI design and a heightened awareness of common errors that developers (and users) can make. From there I joined a company developing pilot and groundcrew training for the Royal Air Force. While I was there, I really started to work on my domain knowledge in earnest. One thing led to another, and I graduated from the University of Lancaster in December 2001 with an MSc. in Advanced Learning Technology. It's a modular course - originally a few of us where I worked at the time were just going to do the first module, but I got carried away!

The course gave a broad overview of technology based training, and subjects that we covered included:

• The psychology of technology-based training
• Analysis and design methods
• Networked learning, collaborative learning, communities of practice
• The use of artificial intelligence in education
• Methods of research and evaluation
• Multimedia courseware engineering
• The organisational context: learning technology integration
• Project management

I've designed training that's delivered either using dedicated software built using packages like Authorware, or via a browser using either XML or HTML. Each approach has its own advantages and disadvantages. The big, purpose-built authoring systems are very flexible, and you can present your content in pretty much any way that your imagination can think up. Their downside is that they're expensive, take time to learn, and produce software that's quite memory intensive. HTML, on the other hand, can be put together with a simple text editor and can be very low-bandwidth. One training programme I worked on recently delivered text and graphics on pages that were never more than 30Kb in size - or about the memory required for one of this site's banner graphics!

One of the big challenges in training is to get people interested in what it is you're trying to teach. One of the biggest challenges for any training designer is how to get the stuff you're teaching to stick. That's one of the reasons why I run this website: by going back and looking at what I've written, I can see whether or not it's useful. I can try my ideas out in the formatting and presentation of text on the screen and see what I like and what looks awful. You'll already have noticed that I tend to keep the design fairly clean - I hate web designers who seem to go out of their way to make text illegible, either through daft colour choices or overpowering backgrounds.

I agree completely - it's why I've spent most of my working life doing it! If you're interested in finding out more, I run a consultancy business that might be able to help you.

Drop me a line at chris (at) chrisharrislearning.com