1. Introduction  
1.1. Vertical structure of disks  
1.2. Radial structure of disks  
2. Data and methods  
2.1. GHOSTS Survey  
2.2. Age selection in the CMD  
2.3. Creating stellar density maps  
2.4. Fitting methods  
2.5. Spitzer data  
3. Results  
3.1. Vertical profiles  
3.2. Radial profiles and 2D fits  
3.3. Discussion of observed profiles  
3.4. Summarizing results  
4. Discussion  
4.1. Possible effects of extinction by gas and dust  
4.3. Disk heating timescales and mechanisms  
4.4. Structural evolution of stellar populations  
4.5. Thin- and thick-disk dichotomy?  
4.6. Breaks  
5. Conclusions and summary