In Proving the Unprovable, Professor Slobogin has done the undoable; he has produced a probing critique of the legal rules for admitting expert mental health testimony that had me turning the pages as if it were a suspense novel. After trenchantly analyzing current stands for admissibility, he suggests innovative approaches to protect the reasonable contributions that mental health experts can make. I doubt that any expert, no matter how experienced, who reads this book will view his or her task on the witness stand in quite the same way again.