The quick answer is no, but really it all depends on who is being deposed. If you’re the one being deposed then yes, as a party you must attend. If it the opposing party your attendance isn’t mandatory but it would help if you heard their version of the story. Realistically I don’t always have my client attend the opposing party’s deposition unless I think they will contest liability and are making up their story as they go along. Sometimes my client’s presence just won’t be helpful.
Bottom line is to ask your attorney what they recommend.
For additional reading visit the Lombardi Law Firm and look in the Client Trial-Deposition Preparation section where you will find articles about depositions and what that means to you, the client.