I'm entering into a contract with 3 other people. We will all sign and date the contract.

My question: do we need to have a fifth person sign as a "witness"? Or are we considered each other's witnesses?

Thanks.

My best advice to you is to contact a lawyer.

I am not an attorney and yes you should consult one but as a general rule I would say, yes, always have a place for a witness to sign...