A solid state lighting device comprising: a base end; at least one solid state emitter; and a heatsink disposed between the base end and the at least one solid state emitter, and arranged to dissipate heat generated by the at least one solid state emitter; wherein: the heatsink has a first heatsink end proximate to the base end, and has a first width at the first heatsink end; the heatsink has a second heatsink end disposed between the base end and the at least one solid state emitter, and has a second width at the second heatsink end; at least a portion of the heatsink disposed between the first heatsink end and the second heatsink end has a third width that is greater than the second width, and the lighting device has a substantially central axis extending in a direction between the base end and an emitter mounting area in which the at least one solid state emitter is mounted; and the heatsink is arranged to permit unobstructed emission of light generated by the at least one solid state emitter according to each emission half-angle of greater than 135 degrees relative to the central axis around an entire lateral perimeter of the solid state lighting device, characterized in that the width of the heatsink increases with distance away from the at least one solid state emitter over the entire heatsink; a base end; at least one solid state emitter; and a heatsink disposed between the base end and the at least one solid state emitter, and arranged to dissipate heat generated by the at least one solid state emitter; wherein: the heatsink has a first heatsink end proximate to the base end, and has a first width at the first heatsink end; the heatsink has a second heatsink end disposed between the base end and the at least one solid state emitter, and has a second width at the second heatsink end; at least a portion of the heatsink disposed between the first heatsink end and the second heatsink end has a third width that is greater than the second width, and the lighting device has a substantially central axis extending in a direction between the base end and an emitter mounting area in which the at least one solid state emitter is mounted; and the heatsink is arranged to permit unobstructed emission of light generated by the at least one solid state emitter according to each emission half-angle of greater than 135 degrees relative to the central axis around an entire lateral perimeter of the solid state lighting device, characterized in that the width of the heatsink increases with distance away from the at least one solid state emitter over the entire heatsink; the heatsink has a first heatsink end proximate to the base end, and has a first width at the first heatsink end; the heatsink has a second heatsink end disposed between the base end and the at least one solid state emitter, and has a second width at the second heatsink end; at least a portion of the heatsink disposed between the first heatsink end and the second heatsink end has a third width that is greater than the second width, and the lighting device has a substantially central axis extending in a direction between the base end and an emitter mounting area in which the at least one solid state emitter is mounted; and the heatsink is arranged to permit unobstructed emission of light generated by the at least one solid state emitter according to each emission half-angle of greater than 135 degrees relative to the central axis around an entire lateral perimeter of the solid state lighting device, characterized in that the width of the heatsink increases with distance away from the at least one solid state emitter over the entire heatsink;