In most studies of human-robot interaction, input devices that are used to give a robot a command have been tested in isolation strictly for their functionality; seldom are comparisons made regarding the ease of use among different input methods. In addition, limited attention is paid as to how certain human capabilities and limitations, or more specifically diminution in hearing, seeing, and motor coordination commonly associated with the aging process, interact with the robot input method, or whether the input method adequately matches the task demands placed on the assistive robot. In this chapter, we attempt to address these areas of robot usability by examining how various agerelated perceptual and motor limitations affect communication with robots. Selecting the right input method can influence older adult adoption rate of assistive robots. Such robots can be instrumental in helping older adults with some of their activities of daily living. We draw from our own previously published empirical studies and those of our colleagues in providing a review of some of the age-related considerations that are pertinent in selecting the right input method for older adult interactions with robots.