A portable ultrasound system having an enhanced user interface is disclosed herein. In one embodiment, a portable ultrasound system can include a hand-held base unit configured to present a graphical user interface that contains a first control area, a second control area, and an active image area. The first control area can have a number of graphical tools that can each be selectively activated by a users finger. The second control area can include a control area having plurality of controls that can be selectively activated by the users thumb to select a tool property of a number of tool properties associated with the selected one of the graphical tools. The active image area can display an ultrasound image, and the selected one of the graphical tools can be overlaid onto the image with the user-selected tool property.