The aim of this paper is to present a concurrent framework for the close integration of automated fixture design and automated fixture assembly activities, which are essential requirements for efficient and agile manufacturing technologies. A new concurrent approach presented in this paper provides significant gains and capability enhancements in these activities. A one-to-one functional mapping of the workholding capability to the fixture design domain has been devised. This is utilized to impose workholding constraints on a complex 3D solid model representation of the workpiece.