Does anyone have a good way to explain why they're not going to sign an NDA? We'll sign as part of signing a contract, but not as part of the initial discussion. I've never found a way to say no without getting a shocked reaction from the requester.
Just ask for an initial conf call to discuss the project, leaving out the most sensitive details. They can decide what is too sensitive. If they won't even tell you the gist of the project without an NDA, they're probably not a good client and you should walk away.
For me the risk just seems too high. I have lots of ideas all the time. The problem with an NDA is that I don't know beforehand what they want to tell me. What if they tell me something I already had as an idea myself, and was looking forward to working on?
Worse, it seems difficult to prove in hindsight what is things they told me and what isn't. An NDA might give them the option to hijack any of my further work by claiming that it is based on something they told me beforehand.
As I've posted above, I've never refused but I have frequently suggested small amendments and explained why I was concerned. It's never been a problem, though in all honesty this has been with mid-sized businesses rather than megacorps.
