An ultrasonic instrument for use during a surgical procedure, comprising: (a) a body defining a longitudinal axis and configured to receive an ultrasonic transducer for selectively generating an ultrasonic oscillation at a first predetermined power level and an ultrasonic oscillation at a second predetermined power level; (b) a shaft assembly projecting from the body, the shaft assembly including an acoustic waveguide configured to communicate the ultrasonic oscillation at the selected first or second predetermined power level therealong; (c) an ultrasonic blade connected to the acoustic waveguide such that the acoustic waveguide communicates the ultrasonic oscillation at the selected first or second predetermined power level to the ultrasonic blade; and (d) an actuation assembly connected to the body and configured to operatively connect to the ultrasonic transducer for selective operation of the ultrasonic blade, the actuation assembly comprising: (i) an activator ring having an outer circumferential surface generally surrounding the body and being selectively moveable relative to the body such that the activator ring is accessible to be gripped by an operator around an entirety of the outer circumferential surface, and (ii) an activation mechanism connected to the activator ring such that the activation mechanism is configured to selectively move relative to the body in conjunction with the activator ring, wherein the activation mechanism includes an activation collar extending longitudinally from the activator ring about the longitudinal axis, and the activation collar is configured to selectively activate the ultrasonic transducer to drive the ultrasonic blade at the selected first or second predetermined power level. (a) a body defining a longitudinal axis and configured to receive an ultrasonic transducer for selectively generating an ultrasonic oscillation at a first predetermined power level and an ultrasonic oscillation at a second predetermined power level; (b) a shaft assembly projecting from the body, the shaft assembly including an acoustic waveguide configured to communicate the ultrasonic oscillation at the selected first or second predetermined power level therealong; (c) an ultrasonic blade connected to the acoustic waveguide such that the acoustic waveguide communicates the ultrasonic oscillation at the selected first or second predetermined power level to the ultrasonic blade; and (d) an actuation assembly connected to the body and configured to operatively connect to the ultrasonic transducer for selective operation of the ultrasonic blade, the actuation assembly comprising: (i) an activator ring having an outer circumferential surface generally surrounding the body and being selectively moveable relative to the body such that the activator ring is accessible to be gripped by an operator around an entirety of the outer circumferential surface, and (ii) an activation mechanism connected to the activator ring such that the activation mechanism is configured to selectively move relative to the body in conjunction with the activator ring, wherein the activation mechanism includes an activation collar extending longitudinally from the activator ring about the longitudinal axis, and the activation collar is configured to selectively activate the ultrasonic transducer to drive the ultrasonic blade at the selected first or second predetermined power level. (i) an activator ring having an outer circumferential surface generally surrounding the body and being selectively moveable relative to the body such that the activator ring is accessible to be gripped by an operator around an entirety of the outer circumferential surface, and (ii) an activation mechanism connected to the activator ring such that the activation mechanism is configured to selectively move relative to the body in conjunction with the activator ring, wherein the activation mechanism includes an activation collar extending longitudinally from the activator ring about the longitudinal axis, and the activation collar is configured to selectively activate the ultrasonic transducer to drive the ultrasonic blade at the selected first or second predetermined power level.