Subtle gender cues play a significant role in determining the contexts or tasks to which robots are preferably assigned. This underscores the importance of gender-sensitive design in developing social robots, a key focus of the RoboGen project. In this project, we aimed to design and develop an assistive socially interactive robot that facilitates gender-sensitive human-robot interaction for older adults. While existing research on gender in Human-Robot Interaction is mainly based on experimental studies, where the robot’s gender is manipulated and participants’ gender assessment is evaluated, we wanted a more contextualized approach. In this article, we report the first phase of the project in which we analyzed requirements for gender sensitivity design through expert interviews as well as a series of workshops with potential senior target users interacting with three different commercially available robotic platforms. Our research demonstrates that gender is a pervasive yet often overlooked factor in Human-Robot Interaction research. Often the gendering process of robots has already taken place before the robots are sold. In our focus groups, we almost found no differences between the three participating groups (women only, men only, mixed) with regard to the two-hour observations of their activities with the robots nor between their statements about the robots. Gender was rarely directly addressed, but circumscribed: It is hidden in statements on the appearance design, voice of robot, name of the robot, tasks the robot is performing etc. Especially with older adults we experienced dominant binary models of gender in their thinking. As also mentioned by our interviewed experts, we see it as our responsibility as researchers to carefully handle these mental models by providing several options of voices (e.g., also a gender-neutral voice), names, tasks the robot performs.