This comes up a couple of times a year so it seems like a post explaining our position on this topic is in order.

We don't sign Non-Disclosure Agreements with prospective clients.

A legal agreement should confer a benefit to one party in exchange for a benefit given to the other party. I enter into a contract to buy a house, I make a monthly mortgage payment. In exchange, I can live in the house or otherwise use it for my benefit. It is equitable. 

An NDA on it's own, without a contract for work, is not an equitable legal arrangement.  

What benefit do I receive by signing an NDA agreement? The right to hear a potential business idea? In exchange, I give up the clear legal right for TD Media to work on a similar project in the future. This isn't equitable and it sets the stage for more inequity in the future.

In my experience, good ideas are pretty common. It is the ability to execute those ideas that is extraordinary. 

So if you want us to sign an NDA, please make sure that there is also a work for hire contract on the table as well. Even a few hours of consulting time may be enough to warrant signing an NDA.