The confidentiality agreement is in many ways the equivalent of a non_disclosure agreement in that it is intended to protect the company from the loss of any confidential information or intellectual property. While the two agreements may be similar in nature, you will find that the major difference between the two are the penalties should an employee breach the contract and divulge any confidential information. The more serious penalties are reserved for a confidentiality agreement and can result in criminal lawsuits and very large fines if not prison sentences.
As you begin to consider putting together a joint venture, you need to sit down together and consider all the different eventualities that can occur. You need to establish your goals and mission statement and put them down in writing. You will also need to list the responsibilities of each of the members of the venture as well so that there can be no mistake in who is responsible for every facet of the day to day operations, at the same time should anything go wrong it can help decide on whose shoulders any blame may fall.