Abstract: The present invention is a sidewall coring assembly and method for taking a core sample at an angle to an existing borehole. The assembly includes a core barrel run at the end of a drill string and having a whipstock suspended below it, the whipstock having an anchor packer at its lower end. The packer is hydraulically inflated through the core barrel and an hydraulic line extending from the bottom thereof, the core barrel is released from the whipstock and the hydraulic line, and lowered to core at the angle and azimuth dictated by the whipstock. After coring is completed, the core barrel is withdrawn from the well and subsequently the whipstock and packer are retrieved with a stinger run on the drill string.