The Talairach-Tournoux (TT) atlas is probably the most often used brain atlas. We overview briefly the activities in developments of electronic versions of the TT atlas and focus on our more than 10-yr efforts in its continuous enhancement resulting in three main versions: TT-1997, TT-2000, and TT-2004. The recent TT-2004 version is substantially improved over the digitized print original with a higher structure parcellation, better quality and resolution of individual structures, and improved three-dimensional (3D) spatial consistency. It is also much more suitable for developing atlas-based applications owing to pure color-coding (for automatic structure labeling), contour representation (to avoid scan blocking by the overlaid atlas), and color cross-atlas consistency (for the simultaneous use of multiple atlases). We also provide a procedure for 3D spatial consistency improvement and illustrate its use. Finally, we present some of our latest atlas-assisted applications for fast and automatic interpretation of morphological, stroke, and molecular images, and discuss the future steps in TT atlas enhancement.