This is a common mistake done by many businesses. You must always sign an NDA with all those vendors to whom you might have to share the latest developments of the company before those are released for your customers.
E.g. you are an engineering product development company and you are going to launch a new machine in the next week. To start the marketing, you will have to share some confidential information with your Content Writers, Graphic Designers and Website Developers.
What if anyone of those vendors accidentally leaks any file or shares this information with your competitors. You are not the only vendor with whom your content writer is working. They work for several businesses and there is a good possibility that they are working with one of your competitors. You will never know this.
An NDA puts a legal obligation on the vendor for not sharing any data without your permission. You can ask your lawyer to prepare a format for the NDA, and ask your vendors to sign it before taking them onboard.
Now that everything has been finalized, it is now time to start the development of the project and track the progress. In my next article I have explained how can you track the progress of your web development project.