Abstract: A two-axis, monolithic, flexure hinge suspension system for an accelerometer or gyroscope has first, second and third cylindrical portions which are slightly axially spaced from each other along a common axis and are connected by pairs of flexible hinges therebetween. Each pair of flexible hinges is mutually perpendicular to another pair of flexible hinges and is also perpendicular to the common axis. Each flexural hinge comprises a pair of flexure leaves extending between adjacent cylindrical portions and joined together at the crossing portions thereof. One of the leaves in the flexure extends downwardly from an arcuate wall of one of the cylindrical portions to an arcuate wall of another cylindrical portion at about a 55.degree. angle to a vertically oriented common axis. The other leaf in the flexure extends upwardly from an arcuate wall portion in the one cylindrical portion to an arcuate wall in the other cylindrical portion at about a 55.degree. angle to the vertically oriented common axis.