Gig magazine (really for rockers) published a survey of their readers about a year ago, showing that groups that did contracts get paid more money. I don't remember the details, but I was impressed.

I do contracts for the more formal events like weddings and receptions. I find that brides generally love contracts because they are so nervous about everything coming together and they appreciate the professionalism. I provide a place for them to sign and ask that they return the contract.

I also write letters of understanding, which do not require a signature by the hiring party.   I especially send these out for the benefits that we do and at the bottom I write our fee, cross it out and write waived. Very often when you play for free people don't understand what they are getting. Sending this letter promotes a professional regard for our band.

I think a simple contract is best, by the way.

Claire