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NDA ( Non Disclosure Agreement )
Service Provider assure that he will not disclose any of the confidential information which he came know about the vendor company / his clients.
This is signed for before hiring IT professional, prior to the interview.
There is not any standard format.
Non-Disclosure Agreement is an agreement whose contents are decided not to be disclosed by both the parties.
However, it is not necessary that it can be only before hiring IT Professionals but it can be signed in respect of a contract, say a contract entered by a Hospital with a Contractor.
A NDA also imposes the duty on both the parties for not disclosing any matter contained in the agreement even after the termination the Contract.
No standard format for Non-Disclosure Agreements is prescribed. It all depends on the business what you do i.e. such as software consulting, multimedia, gaming etc. You can include all the terms and conditions which you feel more appropriate for the company.
A non-disclosure agreement is entered between the parties (mutually disclosed or one 'discloser' and one 'receipient') certain information which are important to the organisation and the leakage of such information may hamper the business of the 'discloser'. This agreement may contain a penalty clause and importantly it should contain 'jurisdiction of the courts' where remedy for breach of contract shall be filed. the format could be tried from any software companies located near to you.