According to my theory, the content of colour harmony has three levels built on one another. The first level is closely related to colour perception. It contains those relations that are identical for almost every person, because they depend on the process of colour perception and can be explained by psycho-physical relations. The second level is the impact of the perceived assembly of colours on the psyche of the perceiving person. On this level the psychological, somatic, age, cultural, social features of the perceiving person also contribute to the development of the value judgment. The third level of the contents of colour harmony is the complex interaction between colours, humans and the environment. Therefore, the value judgment that means the experience of harmony depends on the environment of the assembly of colours, namely on the aspects of lighting, structure, material, but also on location in space and bearing of functions. Colour harmony is always in a direct relationship with the aesthetic function of the environment. The assembly of colours assorted in harmony is the form of the content for which the collection has assembly created.