It happens all the time. I am on an airplane. I strike up a conversation with the woman next to me. I tell her I'm an accountant. It turns out she is in network marketing. Although my acquaintance has only been in the business for a couple of years, she is already making a substantial six-figure income - more money than she has ever made before.

She steers the conversation in the all-too-familiar direction, and starts peppering me with questions: "How can I save on taxes? Should I put my money in a trust? Take it off shore? Set up a pension plan? Can I write off my motorboat?"

Smart people who've worked hard all of their lives to achieve financial success often make dumb estate planning mistakes. Those mistakes can result in their families losing over half of their assets when they pass between generations. They can destroy much of a lifetime's work. And they can inflict a great deal of pain and heartache to the people they love.

The irony is that most of the mistakes are easily avoided. With a little forethought, people of average intellect can construct estate plans which perpetuate their estates for generations. To do that, you and they have to avoid these traps: