Buttons or tabs are function keys on a computer screen that are designed to
facilitate users' direct manipulations. One increasingly popular applicati
on of the button technique in a GIS environment is weighted map overlays fo
r land suitability assessment. Here, buttons are coded with weighting value
s to indicate maps' importance to their associations. There are, however, a
number of flaws in the existing button designs that can affect the quality
of land-suitability assessment. In this paper, we first examine two common
problems of redundancy and underrepresentation in button design, and then
present a button system that is free from these problems.