A method of controlling a powered lower extremity orthotic including an exoskeleton having a waist portion configurable to be coupled to an upper body of a person, at least one leg support configurable to be coupled to a first lower limb of the person, at least one actuator for shifting of the at least one leg support relative to the waist portion to enable movement of the first lower limb of the person, and a plurality of sensors for monitoring the exoskeleton, the method comprising: monitoring a first orientation of said exoskeleton and a second orientation of a second lower limb of the person; and regulating operation of the at least one actuator based on the first and second orientations, and establishing a present state of said exoskeleton from a finite plurality of states and, based on the present state, controlling the at least one actuator to cause the powered lower extremity orthotic to follow a series of orientations collectively reproducing a natural human motion, wherein the leg support includes a thigh segment rotatably connected to the waist portion and a shank segment rotatably connected to the thigh segment, said method further comprising estimating an angle of the shank segment with respect to vertical, wherein the second orientation is the angle of the shank segment with respect to vertical, characterised by further comprising: decomposing an absolute angle of the shank into a sagittal measurement in the sagittal plane and a coronal measurement in the coronal plane; and placing the leg support corresponding to the first lower limb into a state corresponding to taking a step when the sagittal measurement exceeds at least a sagittal threshold and the coronal measurement exceeds at least a coronal threshold, or placing the leg support corresponding to the first lower limb into a state corresponding to taking a step when the angle of the shank segment with respect to gravity exceeds at least a threshold. monitoring a first orientation of said exoskeleton and a second orientation of a second lower limb of the person; and regulating operation of the at least one actuator based on the first and second orientations, and establishing a present state of said exoskeleton from a finite plurality of states and, based on the present state, controlling the at least one actuator to cause the powered lower extremity orthotic to follow a series of orientations collectively reproducing a natural human motion, wherein the leg support includes a thigh segment rotatably connected to the waist portion and a shank segment rotatably connected to the thigh segment, said method further comprising estimating an angle of the shank segment with respect to vertical, wherein the second orientation is the angle of the shank segment with respect to vertical, characterised by further comprising: decomposing an absolute angle of the shank into a sagittal measurement in the sagittal plane and a coronal measurement in the coronal plane; and placing the leg support corresponding to the first lower limb into a state corresponding to taking a step when the sagittal measurement exceeds at least a sagittal threshold and the coronal measurement exceeds at least a coronal threshold, or placing the leg support corresponding to the first lower limb into a state corresponding to taking a step when the angle of the shank segment with respect to gravity exceeds at least a threshold. decomposing an absolute angle of the shank into a sagittal measurement in the sagittal plane and a coronal measurement in the coronal plane; and placing the leg support corresponding to the first lower limb into a state corresponding to taking a step when the sagittal measurement exceeds at least a sagittal threshold and the coronal measurement exceeds at least a coronal threshold, or placing the leg support corresponding to the first lower limb into a state corresponding to taking a step when the angle of the shank segment with respect to gravity exceeds at least a threshold.