As a rule, software systems do not work well until they have been used, and have failed repeatedly, in real applications.

- David Parnas

There are no standards for computer programmers and no group to certify them.

- David Parnas

With software products, it is usual to find that the software has major `bugs' and does not work reliably for some users... The lay public, familiar …

- David Parnas

One bad programmer can easily create two new jobs a year.

- David Parnas

We must not forget that the wheel is reinvented so often because it is a very good idea; I've learned to worry more about the soundness of ideas that…

- David Parnas

Requirements in mathematical language are no use unless they are easier to read than the code.

- David Parnas

I have found that the reason a lot of people are interested in artificial intelligence is the same reason a lot of people are interested in artificia…

- David Parnas

My judgment is that research in 'Star Wars' is going to fail, and I believe this so strongly that I'm willing to stake my professional reputation on …

- David Parnas

Many spend their time berating practitioners for not applying their method. We all need to disseminate our ideas, but most of our time should be spen…

- David Parnas