[ghawkescs]

I believe you should invest in the fields that you work in and understand (as long as you are investing long-term).

Your time and expertise in these areas will give you better insight that most other investors will not have. See Warren Buffett's "circle of competence".

[grp]

The job of Buffet is to buy entire companies. Not so many people has the same job, so his point of view is interesting but should not be common.

[Marazan]

And then: Enron.

[Terr_]

Exactly. Not only were many employees invested in the same sector, their nest-eggs were invested in their employer, which is (from a safety perspective) even worse.

'Course, that invites some comparisons to equity in startups...