CT&A's top window contains a toolbar with icons that open each set of tools in separate windows. The icons are separated in four groups. The first group, with three icons, is associated to the RGB vs RGB tool, a tool which accepts tristimulus type color space inputs such as L*a*b* and RGB. The second group, with one icon, opens the Munsell tools where you can convert FROM and TO Munsell notation. The third group, with eight icons, is associated to tools which require spectral data in order to provide a measurement (CRI, Density, FluoCheck, Graph, ISO 3664+, MI, RAL Design, Whiteness). The last group has one icon, which opens the Help documentation. Opening and closing windows can be done with the toolbar icons or with the "Tools" menu, which contains additional window management functions.