Generally speaking, if you're good enough to get an interview, you should be good enough to get the job. But it's hard for me to assess your interview skills over this format. One thing that you should do is go back to these folks who rejected you and ask them specifically what you need to do to fill in your skills to be a more effective consultant. You really need to get some more specific information you can work with. If you don't know where your skills gaps are, it's impossible to improve. If you approach these folks in a proactive way, they may be impressed by your attitude, and perhaps they can help you to see where your gaps are. Once you know that, you can look to fill them in by getting more training or shifting your project role. With consulting, the hardest job to get is always your first. It sound like you are right on the threshold, so keep at it!
This was first published in May 2005