I found this photo on the website of the British magazine Homes&Gardens. It takes my breath away. Beautiful furniture in a beautiful setting has that effect on me.
The lines of the furniture are wonderful with the pattern of the wallcovering. The colors blend and unify the design. What I like the most about the setting is the mix of modern and traditional styles. The element that makes the mix work is scale. The balance of shapes and sizes is key to creating this wonderful setting.
Without the proper scale and proportion your design plan is lost. The size of the painting over the sofa is proportionally correct. The scale of the wallpaper pattern works with the scale of the curves on the sofa. It all matters and it all contributes to this beautiful setting.