Provided is a technology enabling an imaging apparatus and an interchangeable lens to appropriately perform initialization processes. An interchangeable lens includes a lens control unit configured to transmit lens-side initialization execution element information indicating a plurality of lens-side elements on which the lens control unit itself performs initialization to an imaging apparatus in response to reception of body-side initialization execution element information indicating body-side elements on which the imaging apparatus performs initialization from the imaging apparatus. The technology can be applied to, for example, a camera system including a detachable interchangeable lens and an imaging apparatus serving as a camera body side.